DE102024117892A1 - Chromatography system - Google Patents

Abstract

The present invention describes a chromatography system comprising a first pump, which is connectable to or connected with a liquid reservoir for a first fluid, and a second pump, which is connectable to or connected with a liquid reservoir for a second fluid, wherein the pump outlet lines of the first pump and the second pump are connected by a connector, and a chromatography column is provided downstream of this connector in the direction of flow, and an injection unit is provided upstream of the chromatography column in the direction of flow, wherein the injection unit comprises a sample loop and an injection valve, wherein the injection valve has at least two sample loop ports and two high-pressure ports for supplying and discharging high-pressure fluid, as well as two sample loading ports for loading the sample loop, wherein the sample loop is connectable to or connected with the two sample loop ports of the injection valve, and a third pump is provided, the outlet line of which is connected to a high-pressure port of the injection valve and the inlet line of the third pump is connected via a The pump supply line switching valve is switchable, wherein in a first switching position of the pump supply line switching valve the inlet line of the third pump can be connected to a liquid reservoir for a third fluid, and in a second switching position of the pump supply line switching valve the inlet line of the third pump can be connected to a sample loading port of the addition unit. Furthermore, the present invention describes a chromatography process in which the system is used, as well as a conversion kit for converting a high-performance liquid chromatography system into a chromatography system for supercritical liquid chromatography.

Description

The present invention relates to a chromatography system and a chromatography process.

Chromatographic techniques are important tools for identifying and separating complex samples. The fundamental principle underlying chromatographic techniques is the separation of a mixture into its individual components by transporting the mixture in a moving fluid through a retentive medium. The moving fluid is typically referred to as the mobile phase, and the retentive medium is typically referred to as the stationary phase. The separation of the different constituents of the mixture is based on their differing distributions between the mobile and stationary phases. Differences in the partition coefficients of the components lead to different retention rates at the stationary phase, resulting in separation.

Advanced and now well-established chromatography methods include high-performance liquid chromatography (HPLC) and supercritical fluid chromatography (SFC).

Properly applying the sample to the chromatography column is an essential step for all techniques, but especially for HPLC and SFC, to achieve good and reliable separation.

In HPLC, a sample to be analyzed must be injected into a high-pressure liquid stream, with interruptions to this stream being kept to a minimum. High-pressure injection valves are used for this purpose, enabling virtually seamless switching of the liquid flow. This issue is addressed, for example, in the publication [reference to publication]. DE 10 2008 006 266 A1 as well as the publications cited therein, presented in detail.

Supercritical fluid chromatography (SFC) offers numerous advantages, enabling the simple and reliable separation, chemical analysis, identification, and quantification of various substances. When using carbon dioxide ( _CO₂ ) as the liquid in SFC applications, substance extraction is generally performed above a critical temperature of 31°C and a critical pressure of 74 bar.

To keep _CO₂ or a _CO₂ mixture in a liquid state within a chromatography column, the entire chromatography system must be maintained at a predetermined pressure level. For this purpose, a backpressure regulator is typically provided downstream of the chromatography column and downstream of each detector to maintain the pressure within the chromatography system at a predetermined level.

However, this leads to problems with sample submission. These are mentioned, for example, in the printed materials. US 6,428.70 2B1 and US 6,576,125 B2 Explained in detail.

The well-established HPLC and SFC methods have long been used for both analytical and preparative purposes, and the corresponding equipment is commercially available. However, there is a general desire to improve the characteristics of these systems and methods.

There is a particular interest in increasing the purity of the separated or purified substances. Furthermore, the loss of substances to be separated or purified due to the purification process should be minimized. Additionally, the chromatography system or chromatography method should be capable of processing successive, potentially unrelated samples as quickly as possible and without contamination from previous samples.

In view of the prior art, it is therefore an object of the present invention to provide a chromatography system that solves the problems outlined above. In particular, the system should produce exceptionally pure products obtained with a high yield. Furthermore, the system should have a high throughput, enabling the rapid application and purification of various samples without the need for time-consuming purification cycles.

Furthermore, the substances to be separated should have the smallest possible migration time difference without compromising their separation within the system. Additionally, for a given migration time difference, the system should achieve the highest possible separation of the batches. In particular, the chromatography system should provide excellent separation, resulting in very clear signals for the substances being separated.

Another task is to provide a chromatography system that can be operated and manufactured in a particularly cost-effective and low-maintenance manner.

The system should be as simple and inexpensive to operate as possible and should lead to further cost and handling advantages.

Furthermore, the chromatography system should be as inexpensive as possible in relation to the volume flow rate with which it is operated.

Furthermore, the aim of this invention is to provide a method for carrying out chromatography that achieves the highest possible yield of purified substances. The separated substances should exhibit the highest possible purity. Furthermore, the method should be as simple and cost-effective as possible, leading to further cost and handling advantages.

Furthermore, a high yield and purity of the substances to be separated should be achievable for as many different liquid mixtures or gas-liquid mixtures as possible.

Furthermore, an object of the present invention is to provide components that enable the simplest possible conversion of a known HPLC system to an SFC system. This should also allow for the conversion of preparative HPLC systems.

These and other tasks not explicitly mentioned, which can nevertheless be readily derived or deduced from the contexts discussed in the introduction herein, are solved by a chromatography system with all the features of claim 1.

The present invention accordingly relates to a chromatography system comprising a first pump which is connectable to or connected with a liquid reservoir for a first fluid, and a second pump which is connectable to or connected with a liquid reservoir for a second fluid, wherein the pump outlet lines of the first pump and the second pump are connected with a connecting piece and a chromatography column is provided downstream of this connecting piece in the direction of flow and an injection unit is provided upstream of the chromatography column in the direction of flow.
which is characterized by the fact that
The addition unit comprises a sample loop and an injection valve, wherein the injection valve has at least two sample loop ports and two high-pressure ports for supplying and discharging high-pressure fluid, as well as two sample loading ports for loading the sample loop, wherein the sample loop is connectable to or connected to the two sample loop ports of the injection valve, and a third pump is provided, the outlet line of which is connected to a high-pressure port of the injection valve and the inlet line of the third pump is switchable via a pump inlet switching valve, wherein in a first switching position of the pump inlet switching valve the inlet line of the third pump is connectable to or connected to a liquid reservoir for a third fluid and in a second switching position of the pump inlet switching valve the inlet line of the third pump is connectable to or connected to a sample loading port of the addition unit.

The present invention particularly enables the production of exceptionally pure products with high yields. Furthermore, the system offers high throughput, allowing for the rapid application and purification of various samples without the need for time-consuming cycles for purification and/or equilibration of the chromatographic acid. In particular, the reproducibility of cycles for purification and/or separation of sample compositions is significantly increased, enabling peak prediction with improved accuracy.

In particular, compared to other chromatography systems, this system offers an improvement in that it can achieve very high batch separation even with a given migration time difference. Furthermore, very good separation can be achieved with a relatively small migration time difference between the substances to be separated. In particular, very narrow signals are obtained for the substances being separated during detection.

Even very simply designed pumps can be used, resulting in further investment cost advantages. This applies particularly to the first and second of the pumps described above.

Furthermore, very good results are also achieved with chromatography methods where the system is operated with a gradient. In addition, an SFC process can be carried out even with very different aerosol flow rates without significantly impairing the economic advantages.

Furthermore, the present method and the chromatography system used to carry out the procedure can reduce the complexity and cost of the technical equipment required for setting up SFC analysis. This also allows for the conversion of HPLC systems intended for preparative use.

The chromatography system according to the invention comprises at least two pumps, a first pump and a second pump. The type of pump is irrelevant for the present invention. Rotary lobe pumps, centrifugal pumps, gear pumps, and piston pumps can be used. However, the invention allows the use of cost-effective piston pumps, which preferably comprise at least two pistons. In piston pumps with at least two pistons, the two pistons can be controlled via a camshaft. Furthermore, the two pistons can be controlled independently of each other, with control via a camshaft being often more cost-effective and suitable for the purposes of the present invention. Preferably, the first pump and/or the second pump is designed as a piston pump, with the pump head preferably being coolable. Cooling the pump head is particularly advantageous in a chromatography system designed as an SFC system.

The present invention makes it particularly surprising that excellent separation performance can be achieved even with cost-effective pumps.

The first pump is connectable to, or already connected to, a fluid reservoir for a first fluid, and a second pump is connectable to, or already connected to, a fluid reservoir for a second fluid. The type of fluid reservoir is not specifically limited and can be designed according to the specific requirements.

Preferably, the liquid reservoir for a second fluid and the second pump are provided with a cooling system for the fluid. This embodiment is particularly advantageous in a chromatography system designed as an SFC system. This embodiment ensures that no or only minimal gas formation occurs, which is especially important at relatively low reservoir pressures, such as CO₂ _pressures of 70 bar or less, and particularly 60 bar or less.

The second pump can, in a preferred embodiment, be configured as a system for pumping a compressible liquid. A preferred system for pumping a compressible liquid is described in the prior art, for example, in the publication [reference to publication]. WO 2019/086671 A1 with registration number PCT/ EP2018/080182 with the filing date of November 5, 2018, the disclosure of which is incorporated in its entirety into the present application for disclosure purposes by reference thereto.

The pump outlet lines of the first and second pumps are joined in a connector and routed from this connector into a common outlet line. A chromatography column is installed downstream of this connector, in the direction of flow. Such connectors are well-known and are not subject to any particular limitations.

Viewed in the direction of flow, an injection unit is provided upstream of the chromatography column. Preferably, the injection unit is located downstream of the connecting piece. A sample to be separated is fed into the chromatography system via the injection unit and applied to the chromatography column. The injection unit comprises a sample loop and an injection valve, the injection valve having at least two sample loop ports, two high-pressure ports for supplying and discharging high-pressure fluid, and two sample loading ports for loading the sample loop.

Preferably, the injection valve may comprise eight ports, with two ports serving as sample loop ports, two ports serving as high-pressure ports for supplying and discharging high-pressure fluid, two sample loading ports for loading the sample loop, and two sealed ports. This configuration offers significant advantages, particularly when samples are purified by chromatography over extended periods.

Particularly preferably in an embodiment in which an injection valve with eight ports is used, it can be provided that in a first switching position of the injection valve the two high-pressure ports for supplying and discharging fluid under high pressure are connected to each other, and the two sample loading ports for loading the sample loop are connected to the two sample loop ports, and the two closed ports are connected to each other.

Furthermore, in an embodiment in which an injection valve is used with eight ports, It is particularly preferred that in a second switching position of the injection valve two high-pressure ports for supplying and discharging fluid under high pressure are connected to the two sample loop ports and the two sample loading ports for loading the sample loop are connected to the two closed ports.

The addition unit comprises a sample loop into which a sample to be separated can be introduced, whereby the injection valve is switched to a suitable position. The sample loop is connectable to, or preferably connected to, the injection valve via the two sample loop ports. The sample loop can preferably be filled with a sample by means of a vacuum, this vacuum being generated by the third pump, as described below. The sample loop is preferably emptied by means of pressure generated by the third pump. The volume of the sample loop can be selected according to requirements. Preferably, the volume of the sample loop can be in the range of 0.5 ml to 30 ml, more preferably in the range of 1 ml to 20 ml, and particularly preferably in the range of 2.5 ml to 10 ml.

The chromatography system includes a third pump, wherein the outlet line of the third pump is connected to a high-pressure port of the injection valve and the inlet line of the third pump can be switched via a pump supply line switching valve.

In a first switching position of the pump supply line switching valve, the inlet line of the third pump can be connected to a liquid reservoir for a third fluid, and in a second switching position of the pump supply line switching valve, the inlet line of the third pump can be connected to a sample loading port of the addition unit.

The type of third pump is irrelevant for the present invention, and the pump types described above can be used. Surprising advantages can be achieved by using a stepper motor pump as the third pump. This design allows a sample to be applied to the chromatography column at very low flow rates without any problems regarding precision or efficiency.

The chromatography system of the present invention comprises a pump supply control valve and an injection valve, as described above and below. Preferably, the pump supply control valve and the injection valve can be switched in a coordinated manner. This results in simplified and reliable control of the injection process. For loading the sample loop or for adding a third solvent, which in one embodiment is identical to the first solvent, to the chromatography column, the pump supply control valve and the injection valve can be switched separately.

In a preferred embodiment, it can be provided that in a first switching position of the pump supply line switching valve, the inlet line of the third pump is connected to a liquid reservoir for a third fluid, and the injection valve of the addition unit is switched in a first switching position, wherein the two high-pressure ports for supplying and discharging high-pressure fluid are connected to each other, and the sample loading ports for loading the sample loop are connected to the two sample loop ports. In this first switching position of the injection valve of the addition unit and the first switching position of the pump supply line switching valve, the sample loop is neither loaded nor unloaded with a fluid via the third pump.

Furthermore, it can preferably be provided that in a second switching position of the pump supply line switching valve, the inlet line of the third pump is connected to a sample loading port of the addition unit, and the injection valve of the addition unit is switched in a first switching position, wherein the sample loading ports for loading the sample loop are connected to the two sample loop ports. In this first switching position of the injection valve of the addition unit and the second switching position of the pump supply line switching valve, the sample loop is loaded with a sample via the third pump.

Furthermore, it is preferably provided that in a first switching position of the pump supply line switching valve, the inlet line of the third pump is connected to a liquid reservoir for a third fluid, and the injection valve of the addition unit is switched in a second switching position, wherein the two high-pressure ports for supplying and discharging high-pressure fluid are connected to the two sample loop ports. In this second switching position of the injection valve of the addition unit and the first switching position of the pump supply line switching valve, the sample loop is discharged via the third pump by supplying a third fluid, so that a sample is deposited onto the chromatography column.

Preferably, the pump supply line switching valve may be provided with at least four ports. has one port connected to the inlet line of the third pump, one port connected to a sample loading port for loading the sample loop of the injection valve, one port connected to a fluid reservoir for a third fluid, and one port for depressurization.

It is particularly preferred that the pump supply line switching valve has at least six ports, wherein one port is connected to the inlet line of the third pump, two ports are connected to two sample loading ports for loading the sample loop of the injection valve, one port is connected to a liquid reservoir for a third fluid, one port is connected to a sample container and/or a sample feeder, and one port serves for pressure relief. A pump supply line switching valve with at least six ports enables the use of a system for flushing a sample feeder. A system for flushing a sample feeder typically comprises a liquid reservoir for a fluid and a pump for flushing, which may, for example, be configured as a peristaltic pump, although other pumps may also be used, as described herein. The liquid reservoir for a fluid may preferably comprise a first or a third solvent, as described herein.

During injection, pressure builds up in the sample loop due to the pumped third fluid. If the sample loop is further loaded, this pressure could cause at least some of the third fluid, which is already in the loop, to be transferred into a sample container. This can lead to an undesirable dilution of the sample in the sample container.

In a further embodiment, the pump supply switching valve can have fewer ports, for example three ports, in which case a sample loading port for loading the sample loop of the injection valve can be directly connected to a sample container.

If the pump supply line switching valve has at least 6 ports, it can be provided that in a first switching position of the pump supply line switching valve, the inlet line of the third pump is connected to a liquid reservoir for a third fluid, and a port connected to a sample loading port for loading the sample loop of the injection valve is connected to the port used for pressure relief. In a further embodiment, it can be provided that in a second switching position of the pump supply line switching valve, the inlet line of the third pump is connected to a sample loading port of the addition unit, and the port connected to a sample container is connected to a port connected to a sample loading port for loading the sample loop of the injection valve.

In a preferred embodiment, a second connecting piece may be provided, which, viewed in the direction of flow, is located downstream of the first connecting piece and upstream of the chromatography column. This second connecting piece is connected to the first connecting piece and the chromatography column via a high-pressure port for supplying and discharging high-pressure fluid from the injection valve. Preferably, a check valve is provided between the high-pressure port for supplying and discharging high-pressure fluid from the injection valve and the second connecting piece.

By designing a chromatography system with a previously described addition unit in combination with a third pump, whose inlet line can be switched via a pump inlet control valve, surprising advantages in the performance of the chromatography system can be achieved, as previously explained. These advantages are potentially achieved by enabling the sample application over a small volume. For example, relatively highly concentrated samples can be introduced into a flow that dilutes them sufficiently to prevent precipitate formation. This can be accomplished, for instance, by using a third solvent in which the sample dissolves very well, or by adjusting the flow rate at which the sample is fed into the system. Furthermore, the volume of sample flowing through during application can be minimized. In particular, the sample does not need to pass through the volume of a mixer during application. Additionally, the line between the addition unit or a second connecting piece and the chromatography column can be kept short, thus minimizing unwanted diffusion of the sample during application.

Preferably, the addition unit is controllable via a control system. In a particularly preferred embodiment of the present invention, the chromatography system can comprise several sample containers, wherein the control system of the chromatography system or the addition unit enables samples to be taken from the different sample containers and applied sequentially to the chromatography column. This allows a preferred chromatography system to purify different samples over a longer period and to separate the fractions of different samples into different containers of the fraction collection system. The device or fraction collector is used to collect samples. For example, a sampling needle can take samples from different sample containers. In this case, it may be advantageous to rinse the sampling needle and the lines between the sampling needle and the valve to which the sampling needle is connected. A system for providing different samples, comprising several sample containers so that different samples can be automatically fed to the chromatography system, is also referred to herein as a sample feeder. Preferably, a sample feeder can be connected to a rinsing system to clean the aforementioned sampling needle between different applications.

The chromatography system preferably includes at least one mixer. In a preferred embodiment, a mixer is provided between the connecting piece and the feed unit. If the system includes a second connecting piece, this is located downstream of the mixer and upstream of the chromatography column when viewed in the direction of flow.

If a mixer is used, it can be designed as either an active or passive mixer. Surprising advantages can be achieved through the use of passive mixers. Particularly significant, unpredictable advantages can be obtained by designing the mixer as a static mixer. Static mixers comprise flow-modifying elements that are incorporated into a body with an inlet and an outlet. For example, a tubular body containing inert particles can be used as a static mixer.

The mixer volume can be selected according to the user's needs, generally depending on the system's performance, such as the flow rate it can provide. The higher the flow rate, the larger the preferred mixer volume. Furthermore, the mixer may have a volume in the range of 0.5 ml to 60 ml, preferably in the range of 1 ml to 30 ml.

Furthermore, it may be provided that the system can be used to perform solvent gradient chromatography.

Preferably, the chromatography system can be controlled via a chromatography system control system.

Furthermore, the chromatography system may include at least one detector. Preferably, the chromatography system may include a UV detector. It may also include a mass spectrometer as a detector. In a particularly preferred embodiment, the system includes both a UV detector and a mass spectrometer.

Furthermore, the chromatography system may include a fraction collector or other device through which the purified samples can be collected.

A special embodiment of a fraction collection device, as described below, offers surprising advantages, particularly regarding cost-effectiveness, ease of operation, and verifiability of results. Such a fraction collection device is novel and inventive and is therefore also the subject of the present invention.

A further object of the present invention is a chromatography system comprising a first pump, which is connectable to or connected with a liquid reservoir for a first fluid, and a second pump, which is connectable to or connected with a liquid reservoir for a second fluid, wherein the pump outlet lines of the first pump and the second pump are connected by a connecting piece, and a chromatography column is provided downstream of this connecting piece in the direction of flow, and an injection unit is provided upstream of the chromatography column in the direction of flow, wherein the chromatography system comprises a fraction collection device provided downstream of the chromatography column in the direction of flow, characterized in that the fraction collection device comprises a first fraction switching valve and a second fraction switching valve, wherein the first fraction switching valve has at least four ports, one port of the first fraction switching valve being connected to the outlet line of the chromatography column, one port of the first fraction switching valve being connected to the outlet line of a rinsing pump, and one port of the first fraction switching valve being connected to the outlet line of a rinsing pump. The fraction switching valve is connected to a port of the second fraction switching valve, and a port of the first fraction switching valve is connected to a fraction collector or a waste collection container.

A fraction collection device comprises a first fraction switching valve and a second fraction switching valve, wherein a fraction collection device preferably includes further components for collecting fractions These devices can serve various purposes. For example, a fraction collection device can comprise a few, for example 19 or fewer, preferably 16 or fewer, larger collection vessels, which, depending on the operating mode, serve to collect waste fractions or valuable fractions of a sample. Furthermore, a fraction collection device can have a fraction collector comprising a plurality of smaller collection vessels, for example at least 20, preferably at least 30 or more. It should also be noted that fraction collectors comprising a plurality of smaller collection vessels are often connected to a waste collection vessel, with valuable fractions being directed into the smaller collection vessels via a valve and uninteresting fractions into a waste collection vessel. Therefore, the expression "connected to a fraction collector or a waste collection vessel" is to be understood inclusively.

It should be noted that the features of the second article according to the invention can be combined arbitrarily with the features of the first article, wherein the addition unit of the second article is not limited to the previously described addition unit comprising an injection valve, a third pump and a pump supply line switching valve, but addition units known from the prior art can also be used here as well; for example, suitable addition units are described in the publications DE 10 2008 006266 A1 , WO 2008/107562 A2 , WO 2010/139359 A1 , DE 2020/16100451 U1 , WO 2018/128836 A1 , WO 2013/134222 A1 and EP 4215912 A1 described, wherein for disclosure purposes the description of the addition units set out in these documents is incorporated into the present application by reference thereto. Preferably, however, an addition unit comprising an injection valve, a third pump and a pump supply line switching valve is used, as previously described, wherein the previously described preferred embodiments can also be used, whereby surprising synergies can be achieved, which are particularly evident in a high yield, a high purity and an excellent separation efficiency.

Furthermore, it may be provided that in a first switching position of the first fraction switching valve, the outlet line of the chromatography column is connected to the fraction collector or the waste collection vessel and the outlet line of a rinsing pump is connected to a port of the second fraction switching valve.

Furthermore, it may be provided that in a second switching position of the first fraction switching valve, the outlet line of the chromatography column is connected to a port of the second fraction switching valve.

Furthermore, the first fraction switching valve may have at least five ports, the fifth port being connected to a port of a pump supply line switching valve, as previously described, in particular, in connection with the first subject matter of the present invention. It may also be provided that, in a second switching position of the first fraction switching valve, the outlet line of the chromatography column is connected to a port of the second fraction switching valve, and the outlet line of a rinsing pump is connected to a port of the pump supply line switching valve.

In a particularly preferred embodiment of the present invention, the chromatography system can be configured as an SFC system. In this configuration, the chromatography system preferably comprises a chromatography column and, viewed in the flow direction, at least one backpressure regulator.

It is particularly preferred that a gas-liquid separator be provided downstream of the back pressure regulator when viewed in the direction of flow.

An example of such an SFC chromatography system is operated using supercritical _CO₂ together with a solvent, for example, methanol. Accordingly, a chromatography system designed for supercritical liquid chromatography has at least one storage tank for the solvent and one storage tank for the supercritical fluid, for example, _CO₂ . Generally, the fluid is drawn from the storage tank and transferred by at least one pump to a mixer, which is in fluid communication with a chromatography column. The pumps and/or the mixer, as well as the chromatography column, can be equipped with temperature control to allow for the setting of a predetermined temperature. Heat exchangers can be provided for this purpose. The addition of mixtures to be separated, especially substances to be purified, can be carried out by an addition unit, which is preferably provided in the line through which the solvent is fed to the mixer.

The fluid exiting the chromatography column is preferably at least partially fed to a detection or analysis unit. Examples of detection or analysis units include UV detectors and/or mass spectrometers.

Preferably, the chromatography system includes an injection unit, preferably an injection device, with which samples can be automatically injected into the chromatography system. A preferred embodiment is described above for the first subject matter of the present invention.

The fluid exiting the chromatography column is preferably at least partially fed to a detection or analysis unit. Preferably, the chromatography system may include a UV detector. Furthermore, the chromatography system may include a mass spectrometer as a detector. In a particularly preferred embodiment, the system comprises both a UV detector and a mass spectrometer. Other detection methods can also be employed, such as measuring light scattering, fluorescence, or the refractive index. Mass spectrometers and/or conductivity detectors, etc., are also frequently used. Detectors can also be used for HPLC systems, so these embodiments are applicable to both SFC and HPLC systems.

A backpressure regulator is generally provided downstream of the chromatography column and preferably downstream of the detection or analysis unit, and preferably a heat exchanger is provided downstream of the backpressure regulator. The aerosol leaving the heat exchanger is preferably subsequently fed to a gas-liquid separator.

Preferred gas-liquid separators are those from the state of the art, for example, the printed document. WO 2014/012962 A1 with registration number PCT/ EP2013/06067 with the filing date of 17 July 2013, the disclosure of which is incorporated in its entirety into the present application by reference thereto for disclosure purposes.

A particularly preferred gas-liquid separator is described in the PCT application. WO 2018/210818 A1 with registration number PCT/ EP2018/062537 with the filing date of May 15, 2018, wherein the disclosure of this document, in particular the gas-liquid separators and the preferred embodiments of the gas-liquid separators set forth therein, is fully incorporated into the present application by reference thereto for disclosure purposes. In particular, the embodiments of the gas-liquid separators set forth in the 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 until 9 presented gas-liquid separator, by reference to the PCT application with the application number PCT/ EP2018/062537 inserted into the present application for disclosure purposes.

An unexpected improvement in impact separation can be achieved through the arrangement and design of a separation orifice. This allows, in particular, a reduction in the gas volume supplied during impact separation, thus decreasing the overall volume of the gas-liquid separator. This can surprisingly improve the separation efficiency of the chromatography system.

A preferred gas-liquid separator comprises a separation area with an inlet nozzle, an impact unit, and a gas guide unit.

Preferably, the separation area is designed to effect impact separation. Impact separation means that the liquid droplets contained in the aerosol are directed against an impact unit, allowing the liquid droplets to form a liquid film.

Any body against which the aerosol stream can be directed can serve as an impactor. For example, the aerosol stream can be directed against an upper area of the separation zone, such as the upper edge of the separation zone. A projection, such as a spike or similar, can be provided against which the aerosol stream is directed, so that the liquid droplets directed onto the impactor are not thrown back or rebound from the impactor, but instead form a film.

A preferred gas-liquid separator utilizes gravity during operation to separate the gas and liquid. Accordingly, the term "above" refers to the orientation of the gas-liquid separator during operation, such that gas can flow upwards, while "below" is the opposite direction, through which liquid exits the gas-liquid separator.

In addition to an impact unit, an inlet nozzle is preferably provided in the separation area of the gas-liquid separator. The aerosol is directed through the inlet nozzle into the gas-liquid separator, in particular into the separation area of the gas-liquid separator.

In this case, the inlet nozzle is preferably designed such that a gas-liquid flow guided through the inlet nozzle can be acted upon against the impact unit, as has already been explained previously with regard to the impact unit.

The shape and type of the inlet nozzle are not critical, so it can be selected by a person skilled in the art within the scope of their expertise. For example, the inlet nozzle can be designed to direct the aerosol onto the impact unit in the form of a very narrow jet. Alternatively, the inlet nozzle can also be designed to direct a conical spray onto the impact unit.

The gas-liquid separator preferably has a separation opening arranged between the separation zone and the separation zone, creating a gas- and liquid-open connection between these zones. Inertial separation is preferably effected through the separation opening. This means that the liquid, which flows downwards as a liquid film along the impact unit and/or the gas guide unit, is separated from the gas by inertia. The gas preferably accelerates the liquid, so that the liquid is transferred to the separation zone at a higher velocity than it would be without this gas acceleration. The liquid film preferably remains on a wall of the separation zone, which is preferably designed as part of the impact unit and/or the gas guide unit, and passes directly into the separation zone without leaving this wall. In contrast to the liquid phase, the gas phase does not adhere to a wall but is able to escape upwards and pass into the gas discharge zone. In contrast, the liquid is diverted into the separation zone and removed from the gas-liquid separator via the liquid outlet provided in the separation zone.

Preferably, the distance between the inlet nozzle and the impact unit is greater than the smallest longitudinal dimension of the separation orifice. This distance is determined by the path of the aerosol from the inlet nozzle to the impact unit. The smallest longitudinal dimension of the separation orifice refers to its width or length, where the extent of the plane extending to the edge of the separation orifice is defined as the plane between the separation zone and the separation zone, resulting in a minimum area of the separation orifice. Within this plane, the length of the longest dimension of the separation orifice is determined, allowing the shortest length of the separation orifice, perpendicular to this longest dimension, to be measured. This smallest longitudinal dimension can also be considered the width of the separation orifice.

The spatial shape of the separation area is not critical and can be adapted to specific requirements. A gas guidance unit is preferably formed within the separation area. This gas guidance unit alters the gas flow velocity, resulting in a lower gas velocity at the inlet nozzle than at the separation opening. Since the volumetric flow rate can be considered constant for a given aerosol composition, this means that the aerosol is initially directed into a relatively large space, which is then constricted, thus increasing the flow velocity.

Accordingly, the cross-sectional area of the separation zone can, for example, be circular, preferably narrowing in a wedge shape from the inlet nozzle towards the separation opening. In a preferred embodiment, the separation zone does not have a circular cross-sectional area in the region of the inlet nozzle, and preferably comprises at least three side walls which, together with an upper closure, define a space that is connected to the separation zone via the separation opening.

The gas discharge area serves to drain the gas phase from the gas-liquid separator, so that it includes a gas outlet.

Preferably, the gas discharge area is designed such that the gas velocity at the gas outlet is maximized, and preferably the gas velocity increases in the direction of gas flow from the separation area towards the gas outlet. This creates a suction effect, resulting in reliable and low-maintenance operation of the gas-liquid separator. Furthermore, this allows the volume of the gas-liquid separator to be reduced without compromising its performance in other areas, such as its separation properties.

Reversing the separation area, the space decreases from the direction of the separation zone towards the gas outlet. Preferably, the cross-sectional area tapers accordingly from the direction of the separation zone towards the gas outlet.

Depending on the type of gas, the gas phase of the aerosol can be captured and processed or, for example when using _CO2, released into the environment.

The liquid phase of the aerosol is preferably collected in a fraction collector. The collected fractions are particularly preferably automatically combined as main fractions. The melt, while excess solvent can be subjected to treatment or disposal. Conventional fraction collectors, characterized by a plurality of smaller collection vessels, for example 20, 30 or more, or other fraction collection devices comprising a few, for example 19 or fewer, preferably 16 or fewer, larger collection vessels, can be used, a preferred embodiment comprising both of these configurations, as set forth herein as the second subject matter of the invention. The connecting line between the liquid outlet of the gas-liquid separator and the fraction collector can preferably be designed such that residual gas phase, preferably _CO₂ residue, can escape via this connection. A semipermeable plastic material can be used for this purpose, for example Teflon, particularly preferably AF 2400 (commercially available from DuPont).

A preferred method for operating a fractionation collector in chromatography is described in the prior art, for example in the printed publication. WO 2019/048369 A1 with registration number PCT/ EP2018/073503 with the filing date of 3 September 2018, the disclosure of which is incorporated in its entirety into the present application by reference thereto for disclosure purposes.

Furthermore, it may be provided that the chromatography system includes a chromatography system control unit that is operatively connected to a detector and a fraction collector or fraction collection device.

Preferably, the control system is programmable in such a way that the amount of liquid that can be introduced into a vessel of the fraction collector can be determined depending on the proportion of the first solvent.

Furthermore, the chromatography system may include a chromatography system control unit that is operatively connected to the first pump, whereby the pumping capacity of the first pump can be controlled via the chromatography system control unit. Additionally, the chromatography system control unit may also be operatively connected to the second pump and control its pumping capacity.

Preferably, the chromatography system is designed as an SFC system, whereby chromatography with a solvent gradient can be carried out.

The SFC chromatography system is preferably operable at a flow rate in the range of 10 ml/min to 450 ml/min, particularly preferably in the range of 50 ml/min to 300 ml/min, and especially preferably in the range of 100 ml/min to 250 ml/min. Furthermore, it can be provided that the SFC chromatography system is preferably operable at a flow rate of at least 10 ml/min, particularly preferably at least 50 ml/min, and especially preferably at least 100 ml/min.

Furthermore, the chromatography system can be configured as an HPLC system. An HPLC system differs from an SFC system, among other things, in that an HPLC system does not have a backpressure regulator, which, particularly when viewed in the direction of flow, is located downstream of a chromatography column. Additionally, HPLC systems do not include a gas-liquid separator downstream of the backpressure regulator when viewed in the direction of flow.

According to another aspect, a conversion kit is also provided, which allows a high-performance liquid chromatography (HPLC) system to be converted into a solid fuel cell (SFC) system. Such a kit comprises at least one gas-liquid separator and at least one pump inlet switching valve, as described above. Preferably, the kit includes further components, as described above and below, to convert an HPLC system into an SFC system, such as heat exchangers or backpressure regulators. Preferably, the kit may include a stepper motor pump.

Depending on the specific design of the system to be modified, different components are required. Ideally, one of the pumps in the HPLC system is suitable for operation with a compressible liquid, particularly liquid or supercritical _CO₂ .

Another object of the present invention is a method for carrying out chromatography comprising the use of a chromatography system according to the invention.

Preferably, it can be provided that when loading the sample loop, the pump supply switching valve is switched to the second switching position and the injection valve of the addition unit is switched to a second switching position, wherein the sample loading ports for loading the sample loop are connected to the two sample loop ports, so that the third pump draws the sample to be separated from a sample storage container into the sample loop.

Furthermore, it may be provided that when applying a sample to be separated to the The chromatography column pump supply switching valve is switched to the first switching position and the injection valve of the addition unit is switched to a second switching position, with the sample loading ports for loading the sample loop being connected to the two high-pressure ports for supplying and removing fluid under high pressure, so that the third pump pumps the sample to be separated from the sample loop to the chromatography column with a third solvent.

In a preferred embodiment, gradient chromatography can be performed, wherein the proportion of the first fluid at the beginning of the chromatography is in the range of 0 to 10 vol.% and this proportion of the first fluid is increased, wherein the pump supply switching valve is switched to the first switching position and the injection valve of the addition unit is switched to a first switching position, wherein the two high-pressure ports for supplying and discharging high-pressure fluid are connected to each other, so that the third pump provides at least 50 vol.% of the first fluid at the beginning of the chromatography to form the desired fluid mixture comprising a first and a second fluid.

Furthermore, it may be provided that the fraction collector or fraction collection device is controlled via a control unit and that the control unit is in operative communication with a detector, whereby when a substance is detected by the detector, a control pulse is sent to the fraction collector or fraction collection device, which causes a change of the collection vessel.

In a further embodiment, the fraction collector or fraction collection device can be controlled by a control unit, and the control unit is operatively connected to the detector. After the detector has finished detecting a substance, a control pulse is sent to the fraction collector or fraction collection device, causing a change of the collection vessel. This configuration is preferred over the embodiment in which a change of the collection vessel occurs at the beginning.

In a process using a fraction collection device with a first fraction switching valve and a second fraction switching valve, it can be provided that, when separating uninteresting parts of a sample, the first fraction switching valve is switched to the first switching position and the outlet line of a rinsing pump is connected to a port of the second fraction switching valve, wherein the outlet line of the chromatography column is connected to a waste collection vessel.

Furthermore, in a process using a fraction collection device with a first fraction switching valve and a second fraction switching valve, it can be provided that, when collecting valuable fractions of a sample, the first fraction switching valve is switched to the second switching position and the outlet line of the chromatography column is connected to a port of the second fraction switching valve. In this operating mode, valuable fractions can be collected in a large collection container.

Furthermore, in a process using a fraction collection device with a first fraction switching valve and a second fraction switching valve, it can be provided that, when collecting valuable fractions of a sample, the first fraction switching valve is switched to the first switching position and the outlet line of a rinsing pump is connected to a port of the second fraction switching valve, with the outlet line of the chromatography column being connected to a fraction collector.

Furthermore, in a process using a fraction collection device with a first fraction switching valve and a second fraction switching valve, it can be provided that, when separating uninteresting fractions of a sample, the first fraction switching valve is switched to the second switching position and the outlet line of the chromatography column is connected to a port of the second fraction switching valve. In this operating mode, fractions whose value is uncertain can be collected in a large collection container before final disposal.

In one embodiment, an SFC process is carried out. For this purpose, it can be provided that the liquid reservoir for a first fluid contains a first solvent that is liquid under normal conditions, and the liquid reservoir for a second fluid contains a gaseous solvent under normal conditions. Furthermore, it can be provided that the liquid reservoir for a third fluid contains a third solvent that is liquid under normal conditions. In one embodiment, the third solvent can be identical to the first solvent. Alternatively, the third solvent can differ from the first solvent.

With regard to the term "SFC process" or "supercritical liquid chromium" Regarding the term "supercritical fluid chromatography (SFC)," it should be noted that a supercritical state does not necessarily have to be reached or maintained throughout the entire chromatography process. Rather, the term "SFC method" or "supercritical fluid chromatography (SFC)" means that chromatography is performed using a compressible substance that is easily brought into a supercritical state and is preferably gaseous under normal conditions.

In an SFC method, a solvent composition is preferably pumped into a chromatography column. This composition contains at least a proportion of a first solvent, which is liquid under standard conditions, and a proportion of a second solvent, which is gaseous under standard conditions. This is therefore preferably an SFC as described above and below. Standard conditions are defined as 273.15 K = 0 °C and 1.01325 bar according to DIN 1343.

For separation using a supercritical fluid, an inorganic or organic solvent is employed which is liquid under the usual separation conditions, preferably at 25°C and atmospheric pressure (1013.25 mbar). A polar or nonpolar solvent can be used, depending on the type of compounds to be separated or purified. These substances are referred to herein as the first solvent.

Preferably, the first solvent is selected from an alcohol, preferably methanol, ethanol, or propanol; hexane; mixtures with dichloromethane, chloroform; water (preferably up to a maximum of 3% by volume, as otherwise a miscibility gap may occur); an aldehyde or a ketone, preferably methyl ethyl ketone; an ester, preferably ethyl acetate; or an ether, preferably tetrahydrofuran; an aliphatic hydrocarbon, preferably hexane, cyclohexane, heptane, or octane; or an aromatic hydrocarbon, preferably benzene, toluene, or xylene. These compounds can be used individually or as a mixture.

Furthermore, it may be provided that a gas which can be brought into a supercritical state relatively easily is preferably used in a process according to the invention. Preferred gases exhibiting these properties include, among others, carbon dioxide ( _CO₂ ), ammonia ( _NH₃ ), Freon, and xenon, with carbon dioxide ( _CO₂ ) being particularly preferred. These substances are referred to herein in particular as the second solvent.

Preferably, the gas-liquid mixture to be brought to the supercritical state comprises a polar solvent and a gas selected from the group consisting of _CO₂ , _NH₃ , Freon, Xenon, preferably _CO₂ . Preferably, the polar solvent is an alcohol, preferably methanol, ethanol or propanol, hexane, mixtures with dichloromethane, chloroform, water (preferably up to a maximum of 3 vol%, as otherwise a miscibility gap may occur), an aldehyde or a ketone, preferably methyl ethyl ketone; an ester, preferably ethyl acetate; or an ether, preferably tetrahydrofuran.

Furthermore, the gas-liquid mixture to be brought to the supercritical state may comprise a nonpolar solvent and a gas selected from the group consisting of _CO₂ , _NH₃ , Freon, Xenon, preferably _CO₂ . Preferably, the nonpolar solvent is an aliphatic hydrocarbon, preferably hexane, cyclohexane, heptane, octane; an aromatic hydrocarbon, preferably benzene, toluene, xylene; an ester, preferably ethyl acetate; or an ether, preferably tetrahydrofuran.

The composition flowing from the chromatography column is preferably introduced, at least partially, into a detector. Accordingly, the composition is preferably analyzed downstream of the chromatography column. Detectors suitable for this purpose are generally known, particularly spectroscopic methods using electromagnetic waves, such as UV or Vis spectroscopy. Other detection methods can also be employed, such as measuring light scattering, fluorescence, or the refractive index. Furthermore, mass spectrometers and/or conductivity detectors, etc., are frequently used.

These methods can continuously or batchwise measure the properties of the composition flowing from the chromatography column, allowing these detectors to determine these properties in flow or by sampling, the latter generally being fully automated and continuous. Details of these techniques are known from the prior art, with particular reference to detectors such as those used in conventional HPLC methods.

Preferably, a composition containing the first solvent is obtained after leaving the chromatography column depending on The detector signal is introduced into a collection vessel of the fraction collector or fraction collection device, as described above and below. It is particularly preferred that the amount of liquid introduced into a collection vessel of the fraction collector is selected depending on the proportion of the first solvent.

This measure makes it possible, in particular, to utilize the volume of the fraction collector's collection container in a surprisingly efficient manner. This allows for the previously outlined cost and handling advantages to be achieved.

Further cost and handling advantages can be achieved by preventing at least a portion of the composition containing the first solvent from being discharged into a collection vessel after it leaves the chromatography column. Preferably, compositions that do not contain valuable substances are discarded, generally by means of a control valve in the fraction collector that directs the portions of the composition containing the first solvent to be discarded into a waste container or similar receptacle after it leaves the chromatography column.

In a special embodiment, it may be provided that the solvent composition pumped into a chromatography column is changed during the course of the chromatography.

Preferably, the proportion of the first solvent in the solvent composition is increased during the chromatography process, and the proportion of the second solvent or fluid is decreased. Particularly preferably, the proportion of the first solvent at the beginning of the chromatography is at least 5 vol%, more preferably at least 10 vol%, and most preferably at least 20 vol% lower than the proportion of the first solvent at the end of the chromatography, based on the solvent composition. Accordingly, the proportion of solvent that is liquid under normal conditions preferably increases, while the proportion of solvent that is gaseous under normal conditions decreases. This configuration can surprisingly minimize, and preferably completely prevent, encrustation in a gas separator used in a preferred embodiment of the process. This can surprisingly improve the separation quality of the system or the process.

Furthermore, it may be provided that the proportion of the first solvent is in the range of 5 to 95 vol% and the proportion of the second solvent is in the range of 5 to 95 vol%, based on the solvent composition.

Preferably, the chromatography may be carried out at a pressure in the range of 50 to 500 bar, preferably 75 to 400 bar.

In a preferred embodiment, the chromatography can be carried out at a temperature in the range of 20°C to 80°C, preferably 35°C to 60°C.

In a preferred embodiment of an SFC, the second solvent contained in the composition downstream of the chromatography column can be at least partially separated before being introduced into the fraction collector. This can surprisingly result in a significant improvement in efficiency, since a portion of the solvent is separated before the fraction collector, thus reducing the frequency of vessel changes for the same volume of collection vessels.

The gas-liquid separator can generally be operated at atmospheric pressure. However, to prevent the accumulation of larger quantities of liquid, e.g., methanol, the gas-liquid separator can be operated at a moderate internal back pressure, for example, in the range of 0.1 bar to 25 bar, regulated by a back pressure regulator. Accordingly, the chromatography system can be provided with a back pressure regulator downstream of the gas outlet, preferably adjustable in the range of 1 bar to 25 bar gauge pressure (absolute pressure 2 bar to 21 bar), more preferably 2 bar to 15 bar gauge pressure. Depending on the system design, particularly when recovering the second fluid, e.g., _CO₂, higher back pressures can also be used, in the range of 20 to 60 bar, preferably in the range of 26 to 50 bar, and most preferably in the range of 30 to 40 bar (gauge pressure). The liquid component collected across the separation zone and supplied through the liquid outlet channel enables automated fractionation that can be operated at atmospheric pressure. Using the gas-liquid separator, and similar to conventional HPLC analysis, fully automated fraction collection can also be implemented for SFC analysis.

Accordingly, it may be provided that a gas-liquid separator is used, with the pressure in the gas-liquid separator preferably being in the The pressure range is from 0.1 to 25 bar, preferably from 0.5 to 20 bar, and particularly preferably from 1 to 15 bar (gauge pressure). In a further embodiment, in which, for example, _CO₂ can be recovered, the pressure in the gas-liquid separator can be in the range of 20 to 60 bar, preferably from 26 to 50 bar, and particularly preferably from 30 to 40 bar (gauge pressure).

This design allows for further surprising improvements. In particular, the transit time between the expansion of the solvent mixture and the outlet of the gas-liquid separator is essentially determined by the pressure drop. The gas generated in the small volume causes a high pressure, which is crucial for the transit time. The relative constancy of this pressure leads to high signal integrity, as the transit time remains essentially constant even after expansion when using a suitable gas-liquid separator. Accordingly, especially when using a gas-liquid separator, which can preferably be operated at an overpressure, the addition of solvent, as was previously required to ensure signal integrity, can be omitted. It should be noted that absolute constancy of the gas pressure in the gas-liquid separator is not necessary, as the transit time is very short even at relatively low pressures, so that fluctuations have no significant impact on signal integrity, since this is subject to normal fluctuations due to error tolerances. Pressure fluctuations in the range of 0.1 bar to 25 bar in the gas-liquid separator lead to suitable results, which, depending on the design, can also be higher, for example up to 60 bar, preferably up to 50 bar, and particularly preferably up to 40 bar (overpressure). Preferred embodiments of suitable gas-liquid separators are described above and below, and reference is made to these descriptions.

In a preferred embodiment of the method, in which the chromatography system includes a back pressure regulator by which the pressure in the gas-liquid separator can be controlled, it can be provided that the control of the pressure is selected depending on the solvent content of the gas-liquid mixture; preferably, the control can be designed such that a high pressure is provided in the gas-liquid separator when the solvent content is high.

Preferably, the fractionation process can be operated at a lower pressure than the gas-liquid separator, with the pressure difference preferably being in the range of 0.1 to 60 bar, preferably 0.5 to 40 bar and particularly preferably 1 to 25 bar.

The fractionation is preferably carried out at a pressure in the range of 0 to 1 bar (gauge pressure), particularly preferably 0 to 0.5 bar, and especially preferably 0 to 0.2 bar. The pressure values stated above refer to gauge pressure, which is measured relative to atmospheric pressure.

The detection of a fraction to be collected can be defined in the usual manner, which is generally also used in related chromatographic methods. This includes, for example, collecting a fraction at a specific signal level of the detector, such as a UVNIS detector. Furthermore, a fraction can also be collected based on a specific shape of the signal, such as a predetermined change in the slope of the detector signal or a specific value of the detector signal slope.

Furthermore, the chromatography can be carried out at a flow rate in the range of 10 ml/min to 450 ml/min, particularly preferably in the range of 50 ml/min to 300 ml/min, and especially preferably 100 ml/min to 250 ml/min. This flow rate represents the total flow rate. The flow rate of the individual solvents, in particular the first and second solvents, which are each used as a mixture, is determined by their respective volume fractions.

• 1 eine schematische Darstellung einer Chromatographie-Anlage,
• 2 eine schematische Darstellung einer bevorzugt einsetzbaren Zugabeeinheit und eines Pumpenzuleitungsschaltventils in einer Schaltposition,
• 3 eine schematische Darstellung einer bevorzugt einsetzbaren Zugabeeinheit und eines Pumpenzuleitungsschaltventils in einer weiteren Schaltposition,
• 4 eine schematische Darstellung einer bevorzugt einsetzbaren Zugabeeinheit und eines Pumpenzuleitungsschaltventils in einer weiteren Schaltposition,
• 5 eine schematische Darstellung einer bevorzugt einzusetzenden Fraktionssammel-Vorrichtung mit einem ersten Fraktionsschaltventil und einem zweiten Fraktionsschaltventil,
• 6 eine schematische Darstellung einer bevorzugt einzusetzenden Fraktionssammel-Vorrichtung mit einem ersten Fraktionsschaltventil und einem zweiten Fraktionsschaltventil in einer weiteren Schaltposition,
• 7 eine schematische Darstellung einer als SFC-Anlage ausgestaltete Chromatographie-Anlage,
• 8 eine schematische Darstellung einer weiteren bevorzugt einsetzbaren Zugabeeinheit und eines Pumpenzuleitungsschaltventils in einer Schaltposition,
• 9 eine schematische Darstellung einer weiteren bevorzugt einsetzbaren Zugabeeinheit und eines Pumpenzuleitungsschaltventils in einer weiteren Schaltposition,
• 10 eine schematische Darstellung einer weiteren bevorzugt einsetzbaren Zugabeeinheit und eines Pumpenzuleitungsschaltventils in einer Schaltposition,
• 11 eine schematische Darstellung einer weiteren bevorzugt einsetzbaren Zugabeeinheit und eines Pumpenzuleitungsschaltventils in einer weiteren Schaltposition,
• 12 eine schematische Darstellung einer weiteren bevorzugt einsetzbaren Zugabeeinheit und eines Pumpenzuleitungsschaltventils in einer weiteren Schaltposition,
• 13 eine schematische Darstellung einer weiteren bevorzugt einsetzbaren Zugabeeinheit und eines Pumpenzuleitungsschaltventils in einer Schaltposition,
• 14 eine schematische Darstellung einer weiteren bevorzugt einsetzbaren Zugabeeinheit und eines Pumpenzuleitungsschaltventils in einer weiteren Schaltposition,
• 15 eine schematische Darstellung einer weiteren bevorzugt einsetzbaren Zugabeeinheit und eines Pumpenzuleitungsschaltventils in einer Schaltposition,
• 16 eine schematische Darstellung einer weiteren bevorzugt einsetzbaren Zugabeeinheit und eines Pumpenzuleitungsschaltventils in einer weiteren Schaltposition.

Preferred embodiments of the present invention will now be described by way of example with reference to seven figures, without thereby limiting the invention. The figures show:

• 1 a schematic representation of a chromatography system,
• 2 a schematic representation of a preferably usable addition unit and a pump supply line switching valve in a switching position,
• 3 a schematic representation of a preferably usable addition unit and a pump supply line switching valve in a further switching position,
• 4 a schematic representation of a preferably usable addition unit and a pump supply line switching valve in a further switching position,
• 5 a schematic representation of a preferred fraction collection system Device comprising a first fraction switching valve and a second fraction switching valve,
• 6 a schematic representation of a preferably used fraction collection device with a first fraction switching valve and a second fraction switching valve in a further switching position,
• 7 a schematic representation of a chromatography system designed as an SFC system,
• 8 a schematic representation of another preferably usable addition unit and a pump supply line switching valve in a switching position,
• 9 a schematic representation of another preferably usable addition unit and a pump supply line switching valve in a further switching position,
• 10 a schematic representation of another preferably usable addition unit and a pump supply line switching valve in a switching position,
• 11 a schematic representation of another preferably usable addition unit and a pump supply line switching valve in a further switching position,
• 12 a schematic representation of another preferably usable addition unit and a pump supply line switching valve in a further switching position,
• 13 a schematic representation of another preferably usable addition unit and a pump supply line switching valve in a switching position,
• 14 a schematic representation of another preferably usable addition unit and a pump supply line switching valve in a further switching position,
• 15 a schematic representation of another preferably usable addition unit and a pump supply line switching valve in a switching position,
• 16 a schematic representation of another preferably usable addition unit and a pump supply line switching valve in another switching position.

1 The schematic representation shows a chromatography system 1, such as how it can be designed as an HPLC system.

A suitable chromatography system 1 comprises two fluid streams, wherein a first fluid is supplied by a first liquid reservoir 3 and a second fluid by a second liquid reservoir 5. The two fluids are transferred from the liquid reservoirs 3, respectively, by a first pump 7, which in this case comprises two pistons 7a, 7b, and by a second pump 9, which in this case also comprises two pistons 9a, 9b, respectively, into a connecting piece 11. A mixer 13 is provided downstream of the connecting piece 11 in the direction of flow. A mixer is not a necessary part of a chromatography system according to the invention. However, its inclusion can often yield surprising advantages. Downstream of mixer 13, a second connecting piece 15 is provided through which a sample can be fed into the chromatography system via an injection unit 17. A check valve 16 is provided between connecting piece 15 and injection unit 17 to prevent fluid from mixer 13 from entering the injection unit 17. The injection unit 17 comprises an injection valve 19 and a sample loop 21. The injection valve 19 is connected via lines to a pump supply control valve 23. A third pump 25 is provided in a line between the injection valve 19 and the pump supply control valve 23. Furthermore, the pump supply control valve 23 is connected to a liquid reservoir 27 for a third fluid and to a liquid reservoir 29 for a sample.

The switching positions and connections of the injection valve 19 and the pump supply line switching valve 23 are described in the 2, 3, 4 and 8 to 16 This will be explained in more detail, so reference is made to this.

The first fluid is transferred from liquid reservoir 3 by a pump 7 and the second fluid from liquid reservoir 5 by a pump 9 into the previously described connecting piece 11, so that downstream of the connecting piece 11 a mixture is present which is mixed by a mixer 13 arranged downstream of the connecting piece 11 in the direction of flow. For clarification, it should be noted that the present chromatography system is suitable for carrying out chromatography in which only one fluid is used at the beginning, so the term "mixture" is to be interpreted broadly and is used here only as an example.

A sample is added to the composition after the mixer 13, and this sample is transferred via the second connecting piece 15 to the addition unit 17 in conjunction with the third pump 25 and the pump supply control valve 23 into the chromatography column 31. A fraction collection device 33 is preferably provided after the chromatography column 31.

The fraction collection device 33 can be controlled by one or more control units (not shown here), which are operatively connected to one or more detectors. The detectors are located between the chromatography column 31 and the fraction collection device 33, viewed in the direction of flow.

The term "fraction collection device 33" here encompasses a standard fraction collector with many smaller collection containers, as well as a device such as this one in 5 and 6 which is explained in more detail and includes several larger collection vessels.

2 describes a preferably usable pump supply switching valve 40 and an addition unit 49 with an injection valve 50 in a switching position in which the sample loop 51 is loaded.

In 2 A pump supply line switching valve 40 with eight ports (41, 42, 43, 44, 45, 46, 47, 48) is shown, wherein the ports marked with the symbol "X" (42, 45) are closed. Port 41 serves to release the pressure of pressurized fluid, in particular a third fluid, so that a preferred embodiment of a pump supply line switching valve is shown here. Port 44 is connected to a sample container 38, port 46 to a liquid reservoir 37 for a third fluid, and port 47 to an inlet line of a third pump 36.

The outlet line of the third pump 36 is connected to a high-pressure port 52 of the injection valve 50. The injection valve 50 comprises six ports (52, 53, 54, 55, 56, 57), with two ports (54, 57) configured as sample loop ports, two ports (52, 53) as high-pressure ports for supplying and discharging high-pressure fluid, and two ports (55, 56) as ports for supplying and discharging sample composition and/or fluid into and out of the sample loop. Ports 54 and 57 are connected to the sample loop 51 and configured as sample loop ports. Ports 52 and 53 serve as high-pressure ports for supplying and discharging high-pressure fluid, with port 52 being connected to the outlet line of the third pump 36 and port 53 allowing the sample to be transferred to the chromatography column, which can be done via a second connecting piece, as shown in 1 This will be explained in more detail below. The ports 55 and 56 of the injection valve 50 are connected to ports 43 and 48 of the pump supply line switching valve, so that a sample can be introduced into the sample loop 51 via these ports 55 and 56 and fluid can be discharged from the sample loop.

In one switching position of the pump supply valve 40, the inlet line of the third pump 36 is connected to a sample loop port 56 of the addition unit 49, as is explained in more detail below. This switching position of the injection valve 50 is also referred to herein as the first switching position of the injection valve, and that of the pump supply valve 40 as the second switching position of the pump supply valve.

In this first switching position of the injection valve 50 of the addition unit 49, the sample loop ports (55, 56) for loading the sample loop 51 are connected to the two sample loop ports (54, 57), and in the second switching position of the pump supply line switching valve 40, port 44, to which the sample container 38 is connected, is connected to port 43, and port 47, to which the inlet line of the third pump 36 is connected, is connected to port 48, with ports 43 and 48 of the pump supply line switching valve 40 being connected to ports 55 and 56 respectively of the injection valve 50.

In this switching position, a sample can be introduced into the sample loop 51. In this switching position, port 44 is connected to port 43 of the pump supply line switching valve 40. Furthermore, in the injection valve, port 54 is connected to port 55 and port 56 to port 57. The third pump 36 accordingly draws a sample from sample container 38 into the sample loop 51 via ports 44, 43, 55, and 54, whereby a fluid previously located in the sample loop 51, for example, a third fluid or solvent, is conveyed into the inlet line of the third pump 36 via ports 57, 56, 48, and 47.

After loading sample loop 51, the valves for sample injection are switched, as described in 3 This is explained. This switchover is preferably carried out in a coordinated manner.

3 Figure 40 schematically describes a preferably usable pump supply switching valve 40 and an addition unit 49 with an injection valve 50 in a switching position in which the sample is applied from the sample loop 51 into the chromatography column. As shown in Figure 49, the sample is applied from the sample loop 51 into the chromatography column. 2 As described, the addition unit 49 comprises an injection valve 50 and a sample loop 51, wherein the injection valve 50 has six ports (52, 53, 54, 55, 56, 57). Furthermore, in 3 A pump supply switching valve 40 with eight ports (41, 42, 43, 44, 45, 46, 47, 48) is shown, which is connected to other components, such as a third pump 36, a liquid reservoir 37 for a third fluid, and a sample container 38. These components have been described in more detail previously, with identical reference numerals for the same components. nenten stand so that on 2 Reference is made to the description of these components.

In 3 The injection valve 50 is in a further switching position in which a sample from the sample loop 51 is applied to a chromatography column. This switching position of the injection valve 50 is also referred to herein as the second switching position of the injection valve, and the further position of the pump supply line switching valve 40 is referred to as the first switching position of the pump supply line switching valve.

In this switching position of the pump supply valve 40, the inlet line of the third pump 36 is connected to a liquid reservoir 37 for a third fluid, as is explained in more detail below. The injection valve 50 is switched such that a sample from sample loop 51 is applied to a chromatography column (not shown).

In this second switching position of the injection valve 50 of the addition unit 49, the high-pressure ports (52, 53) for supplying and discharging high-pressure fluid are connected to the two sample loop ports (54, 57), with port 52 connected to port 57 and port 54 to port 53. In the first switching position of the pump supply switching valve 40, port 46, to which the liquid reservoir 37 for a third fluid is connected, is connected to port 47, to which the inlet line of the third pump 36 is connected.

In this switching position of the injection valve 50, a third fluid is pumped by the pump 36 into port 52, so that this fluid transfers a sample from sample loop 51 via port 54 into port 53 through port 57, which is connected to port 52. Port 53 allows the sample to be transferred into the chromatography column, which can be done via a second connection, as shown in 1 will be explained in more detail.

4 describes another combination of the switching positions of the pump supply line switching valve 40 and the injection valve 50. In the 4 In the position combination shown, the pump supply line switching valve 40 is in the first switching position, in which the third fluid is drawn into the inlet line of the third pump and pumped into port 52 of the injection valve 50. The injection valve 50 of the addition unit 49 is switched in a first switching position, with the two high-pressure ports (52, 53) connected for supplying and discharging high-pressure fluid.

In the switching position of the injection valve 50, port 56 is connected to port 57 and port 54 to port 55, with ports 55 and 56 being connected to ports 43 and 48 of the pump supply line switching valve 40. In this switching position of the pump supply line switching valve 40, ports 41 and 48 are connected, with port 41 serving to depressurize the pressurized fluid in the sample loop 51. In the 3 The injection described above is pressure built up in sample loop 51 by means of a pumped third fluid. During the injection in 2 In the described switch position, this pressure could cause the third fluid, located in sample loop 51, to be at least partially transferred into sample container 38 or sample feeder 59. This could lead to an undesirable dilution of the sample in sample container 38 or sample feeder 59. Port 41 can be connected to a container to collect the fluid.

Furthermore, in 4 a further development of the in 2 and 3 The embodiments described are further detailed below. In addition to the components described above, this embodiment includes a system 58 for flushing a sample feeder 59, wherein the sample feeder 59 can be connected to a sample container in a flow-through connection. Preferably, the sample feeder can sequentially extract samples from two or more sample containers, so that flushing of the sample feeder is advantageously carried out when the sample containers are changed. This is explained in more detail below. This can be done in the first switching position of the pump supply valve 40, wherein a fluid, preferably a third fluid, is pumped into the sample feeder 59 via ports 45 and 44.

5 a schematic representation of a preferred fraction collection device with a first fraction switching valve and a second fraction switching valve in a switching position in which a fraction from a chromatography column is directed into the second fraction switching valve.

In 5 A preferred fraction collection device 61 is shown with a first fraction switching valve 63, wherein the first fraction switching valve 63 comprises six ports (65, 66, 67, 68, 69, 70). Port 66 of the first fraction switching valve 63 is connected to a second fraction switching valve 72, and port 64 to a chromatography column 84. Depending on the configuration of the chromatography system, further components thereof may be provided between the chromatography column and port 65, such as detectors and, in the case of SFC, a back pressure regulator and a gas-liquid separator, which are not present in HPLC. Depending on the configuration of the system, port 70 is connected to Port 67 is connected to a fraction collector 82, which preferably comprises a plurality of smaller collection vessels, or to a waste collection vessel 82. Port 67 is connected to the outlet line of a flushing pump 86, which in turn is connected to a liquid reservoir for a fluid. In the present embodiment, port 68 of the first fraction switching valve 63 is connected to a port of a pump supply switching valve, which is not shown.

In the 5 In the switching position of the first fraction switching valve 63 shown, a fluid pumped by the flushing pump 86 via port 67 and port 68 can be used to flush the in 4 The sample introduction described above serves as the basis for further analysis, so reference is made to it and the information contained therein. 5 The presented flushing pump 86 can serve as a system for flushing a sample feeder.

The second fraction switching valve 72 comprises an inlet port 74, which is connected to port 66 of the first fraction switching valve 63 and through which fluid can be directed from the first fraction switching valve 63 into the second fraction switching valve 72. Furthermore, the second fraction switching valve 72 comprises several outlet ports 76, each connected to a preferably large collection vessel 78, through which fractions can be collected. For clarity, only one collection vessel 78 is shown, but a plurality of outlet ports 76. In the present illustration, a fraction to be collected is directed into the collection vessel 78 via the inlet port 74. To collect the next fraction, the second fraction switching valve 72 can be switched so that the fraction is directed into another collection vessel (not shown).

In the switching position of the first fraction switching valve 63 shown here, fluid which is directed from the chromatography column 84 via port 65 into the first fraction switching valve 63 is transferred via port 66 into port 74 of the second fraction switching valve 72 and via port 76 into a collection vessel 78.

In this switching position, port 67 is connected to port 68, so that the flushing pump 86 can be used to flush a sample feeder, as is the case in 4 has been explained.

6 Figure 1 shows a schematic representation of a preferably used fraction collection device with a first fraction switching valve and a second fraction switching valve in a further switching position, in which a fraction from a chromatography column is directed into a fraction collector or a waste collection container.

The in 6 The components presented essentially correspond to those described in 5 are set out, where the same reference symbols describe the same components.

In the 6 In the switching position of the first fraction switching valve 63 shown, fluid which is directed from the chromatography column 84 via port 65 into the first fraction switching valve 63 is transferred via port 70 into a fraction collector or a waste container 82.

In this switching position, port 67 is connected to port 66, so that the flushing pump 86 can be used to flush the second fraction switching valve 72, starting from port 67 of the first fraction switching valve 63 to the respective connected collection vessel 78.

The in 5 and 6 The fraction collection device 61 shown can preferably be used to advantage in two operating modes, which are described below.

In a first operating mode, this fraction collection device 61 enables the efficient use of large collection containers 78, such as those connected to the second fraction switching valve 72. Typically, when using large collection containers, waste fractions are collected between the containers for valuable fractions.

In the first operating mode, the described fraction collection device 61 enables waste fractions to be collected via the in 6 The fluid is directed into a waste collection vessel 82 in the switching position of the first fraction switching valve 63 shown. In this position, the line starting from port 67 of the first fraction switching valve 63 can be flushed with fluid, so that when the next position for collecting a valuable fraction is reached, no residues are present in the line between port 66 of the first fraction switching valve 63 and the next collection vessel 78, and these can be directed into the next collection vessel 78, as shown in 5 is shown.

In a second operating mode, this fraction collection device 61 allows fractions to be collected between the valuable fractions in order to test them again before discarding the waste fraction. This is particularly useful if complex detection systems are not available.

In a second operating mode, valuable fractions are stored in the 6 In the switching position of the first fraction switching valve 63 shown, the mixture is directed into a fraction collector 82. tion The line can be flushed with fluid starting from port 67 of the first fraction switching valve 63 to prevent cross-contamination between possible waste fractions. In the 5 In the switching position shown, different waste fractions are directed into the second fraction switching valve 72 and from there transferred into different collection containers 78.

7 Figure 1 shows a schematic representation of a chromatography system 100 with a gas-liquid separator 130, which is suitable for supercritical liquid chromatography.

Such a system is described using supercritical _CO₂ as an example, with methanol being presented as an exemplary solvent. Naturally, systems using other solvents, preferably organic solvents, or other supercritical fluids, are similarly constructed.

As in 7 As shown, the respective fluids are stored in reservoirs. In particular, the gas used in a supercritical state can be stored in a storage tank 102, and the solvent in a storage tank 104. These fluids can be pumped from storage tanks 102 and 104, respectively, to the other components of the system via pumps 106 and 108. In the system 100 described here, a preparation stage 110 or 112 is preferably provided in each fluid supply line, through which the liquids can be tempered. Furthermore, a leveling stage for pressure fluctuations caused by the pumps can be provided. Accordingly, this preparation stage can, for example, be designed as a heat exchanger or as a pump. The fluids taken from storage tanks 102 and 104 are directed into a connecting piece 114 and subsequently into a mixer 115.

Downstream of the mixer, a second connecting piece 116 is provided, through which a sample can be supplied to the chromatography system 100, which is then applied to the chromatography column 120. Reference numeral 117 symbolizes a feed unit, a preferred embodiment of which is described above in 2 , 3 and 4 as further described and which may include additional components, including a third pump whose inlet line can be switched via a pump inlet control valve. These components are not shown in detail here for the sake of clarity, so reference is made to the figures presented above. The liquid reservoir 118 for a third fluid and a sample container 119 are in fluid connection with the components shown by reference numeral 117, as described in detail above. 2 , 3 and 4 is described in more detail.

In the present system 100, two analysis units are connected downstream of the chromatography column 120. A sample discharge unit 121 is connected to a mass spectrometer 122, and a UV detector 124 is provided downstream of the sample discharge unit. Downstream of the analysis unit, a device for providing an additional volume 125 is provided, which serves in particular to increase the flow time of the liquid in order to evaluate results, for example, from the mass spectrometer 122. The backpressure regulator 126 provided in the line downstream of the device for providing the additional volume 125 maintains the respective pressure necessary to keep the fluid in a supercritical state. A heat exchanger 128 is provided downstream of the backpressure regulator 126, which prevents the aerosol from freezing during the decompression process. Subsequently, the aerosol is introduced into a gas-liquid separator 130, with the gas from the system being discharged via outlet 132.

The liquid is introduced into a fraction collector or fraction collection device 134 and fractionated therein. The solvent contained in the fractionated samples can be removed from the samples.

8 describes another preferably usable pump supply switching valve 140 and an addition unit 139 with an injection valve 50 in a switching position in which the sample loop 51 is loaded.

In 8 A pump supply line switching valve 140 with four ports (142, 144, 146, 148) is shown. It is obvious to those skilled in the art that a valve with more ports can also be used, in which case ports must be closed or connected to each other in a suitable manner. Port 146 serves to release pressure from a pressurized fluid, in particular a third fluid, so that a preferred embodiment of a pump supply line switching valve is shown here. Port 148 is connected to a fluid reservoir 137 for a third fluid, and port 142 is connected to an inlet line of a third pump 136.

The outlet line of the third pump 136 is connected to a high-pressure port 52 of the injection valve 50. The injection valve 50 comprises 6 ports (52, 53, 54, 55, 56, 57), with two ports (54, 57) serving as sample loop ports, two ports (52, 53) serving as high-pressure ports for supplying and discharging high-pressure fluid, and two ports (55, 56) serving as ports for supplying and discharging sample composition and/or fluid. The sample loop is configured as follows: Ports 54 and 57 are connected to sample loop 51 and are configured as sample loop ports. Ports 52 and 53 serve as high-pressure ports for supplying and discharging high-pressure fluid. Port 52 is connected to the outlet line of the third pump 36, and port 53 allows the sample to be transferred to the chromatography column via a second connecting piece, as shown in [reference missing]. 1 This will be explained in more detail below. Port 55 of the injection valve 50 is connected to a sample container 138 and port 56 of the injection valve is connected to port 144 of the pump supply line switching valve, so that a sample can be introduced into the sample loop 51 via these ports 55 and 56 and fluid can be discharged from the sample loop.

In one switching position of the pump supply line switching valve 140, the inlet line of the third pump 136 is connected to a sample loop port 56 of the addition unit 139, as is explained in more detail below. This switching position of the injection valve 50 is also referred to here as the first switching position of the injection valve, and that of the pump supply line switching valve 140 as the second switching position of the pump supply line switching valve.

In this first switching position of the injection valve 50 of the addition unit 139, the sample loop ports (55, 56) for loading the sample loop 51 are connected to the two sample loop ports (54, 57) and in the second switching position of the pump supply line switching valve 140, port 142, to which the inlet line of the third pump 36 is connected, is connected to port 144, to which port 56 of the injection valve is connected.

In this switching position, a sample can be introduced into the sample loop 51. In this switching position, port 142 is connected to port 144 of the pump supply line switching valve 140. Furthermore, in the injection valve, port 54 is connected to port 55 and port 56 to port 57. Accordingly, the third pump 136 draws a sample from sample container 138 into the sample loop 51 via ports 55 and 54, whereby a fluid previously located in the sample loop 51, for example, a third fluid or solvent, is conveyed via ports 57, 56, 144, and 142 into the inlet line of the third pump 136.

After loading sample loop 51, the valves for sample injection are switched, as described in 9 This is explained. This switchover is preferably carried out in a coordinated manner.

9 Figure 1 schematically describes a preferably usable pump supply line switching valve 140 and an addition unit 139 with an injection valve 50 in a switching position in which the sample is applied from the sample loop 51 into the chromatography column. As in 8 As described, the addition unit 139 comprises an injection valve 50 and a sample loop 51, wherein the injection valve 50 has six ports (52, 53, 54, 55, 56, 57). Furthermore, in 9 A pump supply switching valve 140 with four ports (142, 144, 146, 148) is shown, which is connected to other components, such as a third pump 136 and a fluid reservoir 137 for a third fluid. These components have been described in more detail previously, with identical reference numerals representing the same components, so that 8 Reference is made to the description of these components.

In 9 The injection valve 50 is in a further switching position in which a sample from the sample loop 51 is applied to a chromatography column. This switching position of the injection valve 50 is also referred to herein as the second switching position of the injection valve, and the further position of the pump supply line switching valve 140 is referred to as the first switching position of the pump supply line switching valve.

In this switching position of the pump supply valve 140, the inlet line of the third pump 136 is connected to a liquid reservoir 137 for a third fluid, as is explained in more detail below. The injection valve 50 is switched such that a sample from sample loop 51 is applied to a chromatography column (not shown).

In this second switching position of the injection valve 50 of the addition unit 139, the high-pressure ports (52, 53) for supplying and discharging high-pressure fluid are connected to the two sample loop ports (54, 57), with port 52 connected to port 57 and port 54 to port 53. In the first switching position of the pump supply switching valve 140, port 148, to which the liquid reservoir 137 for a third fluid is connected, is connected to port 142, to which the inlet line of the third pump 136 is connected.

In this switching position of the injection valve 50, a third fluid is pumped by the pump 136 into port 52, so that this fluid transfers a sample from sample loop 51 via port 54 into port 53 through port 57, which is connected to port 52. Port 53 allows the sample to be transferred into the chromatography column, which can be done via a second connector, as shown in 1 will be explained in more detail.

10 describes another combination of the switching positions of the pump supply line switching valve 140 and the injection valve 50. In the 10 In the position combination shown, the pump supply line switching valve 140 is in the first switching position, in which the third fluid is drawn into the inlet line of the third pump and pumped into port 52 of the injection valve 50. The injection valve 50 of the addition unit 139 is switched in a first switching position, with the two high-pressure ports (52, 53) connected for supplying and discharging high-pressure fluid.

In the switching position of the injection valve 50, port 56 is connected to port 57 and port 54 to port 55, with port 55 being connected to a sample container 138 and port 56 to port 144 of the pump supply switching valve 140. In this switching position of the pump supply switching valve 140, ports 144 and 146 are connected, with port 146 serving to depressurize the pressurized fluid in the sample loop 51. In the 9 The injection described above is pressure built up in sample loop 51 by means of a pumped third fluid. During the injection in 8 In the described switch position, this pressure could cause the third fluid, located in sample loop 51, to be at least partially transferred into sample container 138. This could lead to an undesirable dilution of the sample in sample container 138. Port 146 can be connected to a container to collect the fluid.

11 describes another preferably usable pump supply switching valve 160 and an addition unit 139 with an injection valve 50 in a switching position in which the sample loop 51 is loaded.

In 11 A pump supply switching valve 160 with three ports (162, 164, 166) is shown. Port 166 is connected to a fluid reservoir 137 for a third fluid and port 162 to an inlet line of a third pump 136.

The outlet line of the third pump 136 is connected to a high-pressure port 52 of the injection valve 50. The injection valve 50 comprises six ports (52, 53, 54, 55, 56, 57), with two ports (54, 57) configured as sample loop ports, two ports (52, 53) as high-pressure ports for supplying and discharging high-pressure fluid, and two ports (55, 56) as ports for supplying and discharging sample composition and/or fluid into and out of the sample loop. Ports 54 and 57 are connected to the sample loop 51 and configured as sample loop ports. Ports 52 and 53 serve as high-pressure ports for supplying and discharging high-pressure fluid, with port 52 being connected to the outlet line of the third pump 136 and port 53 allowing the sample to be transferred to the chromatography column, which can be done via a second connecting piece, as shown in 1 This will be explained in more detail below. Port 55 of the injection valve 50 is connected to a sample container 138 and port 56 of the injection valve is connected to port 164 of the pump supply line switching valve, so that a sample can be introduced into the sample loop 51 via these ports 55 and 56 and fluid can be discharged from the sample loop.

In one switching position of the pump supply line switching valve 160, the inlet line of the third pump 136 is connected to a sample loop port 56 of the addition unit 138, as is explained in more detail below. This switching position of the injection valve 50 is also referred to herein as the first switching position of the injection valve, and that of the pump supply line switching valve 160 as the second switching position of the pump supply line switching valve.

In this first switching position of the injection valve 50 of the addition unit 139, the sample loop ports (55, 56) for loading the sample loop 51 are connected to the two sample loop ports (54, 57) and in the second switching position of the pump supply line switching valve 160, port 162, to which the inlet line of the third pump 136 is connected, is connected to port 164, to which port 56 of the injection valve is connected.

In this switching position, a sample can be introduced into the sample loop 51. In this switching position, port 162 is connected to port 164 of the pump supply switching valve 160. Furthermore, in the injection valve, port 54 is connected to port 55 and port 56 to port 57. Accordingly, the third pump 136 draws a sample from sample container 138 into the sample loop 51 via ports 55 and 54, whereby a fluid previously located in the sample loop 51, for example, a third fluid or solvent, is conveyed via ports 57, 56, 164, and 162 into the inlet line of the third pump 136.

After loading sample loop 51, the valves for sample injection are switched, as described in 12 This is explained. This switchover is preferably carried out in a coordinated manner.

12 Figure 1 schematically describes a preferably usable pump supply switching valve 160 and an addition unit 139 with an injection valve 50 in a switching position in which the sample is applied from the sample loop 51 into the chromatography column. As in 11 As described, the addition unit 139 comprises an injection valve 50 and a sample loop 51, wherein the injection valve 50 comprises six ports (52, 53, 54, 55, 56, 57). Furthermore, in 12 A pump supply switching valve 160 with three ports (162, 164, 166) is shown, which is connected to further components, such as a third pump 136 and a fluid reservoir 137 for a third fluid. These components have been described in more detail previously, with identical reference numerals representing the same components, so that on 11 Reference is made to the description of these components.

In 12 The injection valve 50 is in a further switching position in which a sample from the sample loop 51 is applied to a chromatography column. This switching position of the injection valve 50 is also referred to herein as the second switching position of the injection valve, and the further position of the pump supply line switching valve 160 is referred to as the first switching position of the pump supply line switching valve.

In this switching position of the pump supply valve 160, the inlet line of the third pump 136 is connected to a liquid reservoir 137 for a third fluid, as is explained in more detail below. The injection valve 50 is switched such that a sample from sample loop 51 is applied to a chromatography column (not shown).

In this second switching position of the injection valve 50 of the addition unit 139, the high-pressure ports (52, 53) for supplying and discharging high-pressure fluid are connected to the two sample loop ports (54, 57), with port 52 connected to port 57 and port 54 to port 53. In the first switching position of the pump supply switching valve 160, port 166, to which the liquid reservoir 137 for a third fluid is connected, is connected to port 162, to which the inlet line of the third pump 136 is connected.

In this switching position of the injection valve 50, a third fluid is pumped by the pump 136 into port 52, so that this fluid transfers a sample from sample loop 51 via port 54 into port 53 through port 57, which is connected to port 52. Port 53 allows the sample to be transferred into the chromatography column, which can be done via a second connector, as shown in 1 will be explained in more detail.

13 describes a preferably usable pump supply switching valve 240 and an addition unit 249 with an injection valve 250 in a switching position in which the sample loop 251 is loaded.

In 13 A pump supply line switching valve 240 with eight ports (241, 242, 243, 244, 245, 246, 247, 248) is shown, with port (242) marked with the symbol "X" being closed. Port 241 serves to release pressure from a pressurized fluid, in particular a third fluid, so that a preferred embodiment of a pump supply line switching valve is shown here. Port 244 is connected to a sample feeder 280, port 246 to a liquid reservoir 237 for a third fluid, and port 247 to an inlet line of a third pump 236. Sample feeder 290 can comprise several sample containers (not shown in detail) from which different samples can be supplied to the chromatography system via a sampling needle. Furthermore, the embodiment presented here includes a system 280 for rinsing the sample feed 290, which is connected to the pump supply switching valve 240 via port 245.

The outlet line of the third pump 236 is connected to a high-pressure port 253 of the injection valve 250. The injection valve 250 comprises 8 ports (252, 253, 254, 255, 256, 257, 258, 259), with two ports (252, 255) being designed as sample loop ports, two ports (253, 254) as high-pressure ports for supplying and discharging high-pressure fluid, and two ports (256, 259) as ports for supplying and discharging sample composition and/or fluid into and out of the sample loop. The ports marked with the symbol "X" (257, 258) are closed.

Here, ports 252 and 255 are connected to the sample loop 251 and are configured as sample loop ports. Ports 253 and 254 serve as high-pressure ports for supplying and discharging high-pressure fluid, with port 253 being connected to the outlet line of the third pump 236 and port 254 allowing the sample to be transferred to the chromatography column via a second connector, as shown in 1 This will be explained in more detail below. The ports 256 and 259 of the injection valve 250 are connected to ports 243 and 248 of the pump supply line switching valve 240, so that a sample can be introduced into the sample loop 251 via these ports 256 and 259 and fluid can be discharged from the sample loop.

In one switching position of the pump supply line switching valve 240, the inlet line of the third pump 236 is connected to a sample loop port 256 of the addition unit 249, as is explained in more detail below. This switching position of the injection valve 250 is also referred to herein as the first switching position of the injection valve, and that of the pump supply line switching valve 240 as second switching position of the pump supply valve.

In this first switching position of the injection valve 250 of the addition unit 249, the sample loop ports (256, 259) for loading the sample loop 251 are connected to the two sample loop ports (252, 255), and in the second switching position of the pump supply switching valve 240, port 244, to which the sample feeder 290 is connected, is connected to port 243, and port 247, to which the inlet line of the third pump 236 is connected, is connected to port 248, with ports 243 and 248 of the pump supply switching valve 40 being connected to ports 256 and 259 respectively of the injection valve 250.

In this switching position, a sample can be introduced into the sample loop 251. In this switching position, port 244 is connected to port 243 of the pump supply switching valve 240. Furthermore, in the injection valve, port 256 is connected to port 255 and port 252 to port 259. Accordingly, the third pump 36 draws a sample from sample feeder 290 into the sample loop 251 via ports 244, 243, 256, and 255, whereby a fluid previously located in the sample loop 251, for example, a third fluid or solvent, is conveyed via ports 252, 259, 248, and 247 into the inlet line of the third pump 236.

In addition to the components described above, this embodiment includes a system 280 for flushing a sample feeder 290, wherein the sample feeder 290 can be connected to a sample container via a flow path. Preferably, the sample feeder can sequentially draw samples from two or more sample containers, so that flushing of the sample feeder is advantageously performed when changing the sample containers. This is explained in more detail below. This can be done in the first switching position of the pump supply valve 240, wherein a fluid, preferably a third fluid, is pumped into the sample feeder 290 via ports 245 and 244.

After loading sample loop 251, the valves for sample injection are switched, as described in 14 This is explained. This switchover is preferably carried out in a coordinated manner.

14 Figure 1 schematically describes a preferably usable pump supply switching valve 240 and an addition unit 249 with an injection valve 250 in a switching position in which the sample is applied from the sample loop 251 into the chromatography column. As shown in Figure 249, the sample is applied from the sample loop 251 into the chromatography column. 13 As described, the addition unit 249 comprises an injection valve 250 and a sample loop 251, wherein the injection valve 250 comprises eight ports (252, 253, 254, 255, 256, 257, 258, 259). Furthermore, in 14 A pump supply switching valve 240 with eight ports (241, 242, 243, 244, 245, 246, 247, 248) is shown, which is connected to other components, such as a third pump 236, a liquid reservoir 237 for a third fluid, a system 280 for rinsing a sample feeder 290, and a sample feeder 290. These components have been described in more detail previously, with identical reference numerals representing the same components, so that on 13 Reference is made to the description of these components.

In 14 The injection valve 250 is in a further switching position in which a sample from the sample loop 251 is applied to a chromatography column. This switching position of the injection valve 250 is also referred to herein as the second switching position of the injection valve, and the further position of the pump supply line switching valve 240 is referred to as the first switching position of the pump supply line switching valve.

In this switching position of the pump supply valve 240, the inlet line of the third pump 236 is connected to a liquid reservoir 237 for a third fluid, as is explained in more detail below. The injection valve 250 is switched such that a sample from sample loop 251 is applied to a chromatography column (not shown).

In this second switching position of the injection valve 250 of the addition unit 249, the high-pressure ports (253, 254) for supplying and discharging high-pressure fluid are connected to the two sample loop ports (252, 255), with port 253 connected to port 252 and port 254 to port 255. In the first switching position of the pump supply switching valve 240, port 246, to which the liquid reservoir 237 for a third fluid is connected, is connected to port 247, to which the inlet line of the third pump 236 is connected.

In this switching position of the injection valve 250, a third fluid is pumped by the pump 236 into port 253, so that this fluid transfers a sample from sample loop 251 via port 255 into port 254 via port 252, which is connected to port 253. Port 254 allows the sample to be transferred into the chromatography column, which can be done via a second connection, as shown in 1 will be explained in more detail.

15 describes another combination of the switching positions of the pump supply switching valve 240 and the injection valve 250.

As in 13 As described, the addition unit 249 comprises an injection valve 250 and a sample loop 251, wherein the injection valve 250 comprises eight ports (252, 253, 254, 255, 256, 257, 258, 259). Furthermore, in 15 A pump supply switching valve 240 with eight ports (241, 242, 243, 244, 245, 246, 247, 248) is shown, which is connected to other components, such as a third pump 236, a liquid reservoir 237 for a third fluid, a system 280 for rinsing a sample feeder 290, and a sample feeder 290. These components have been described in more detail previously, with identical reference numerals representing the same components, so that on 13 Reference is made to the description of these components.

In the 15 In the position combination shown, the pump supply line switching valve 240 is in the first switching position, in which the third fluid is drawn into the inlet line of the third pump and pumped into port 253 of the injection valve 250. The injection valve 250 of the addition unit 249 is switched in a first switching position, with the two high-pressure ports (253, 254) connected for supplying and discharging high-pressure fluid.

In the switching position of the injection valve 250, port 252 is connected to port 259 and port 255 to port 256, with ports 259 and 256 being connected to ports 243 and 248 of the pump supply switching valve 240. In this switching position of the pump supply switching valve 240, ports 241 and 248 are connected, with port 241 serving to depressurize the pressurized fluid in the sample loop 251. In the 14 The injection described above is pressure built up in sample loop 251 by means of a pumped third fluid. During the injection in 13 In the described switch position, this pressure could cause the third fluid, located in sample loop 251, to be at least partially transferred into sample feeder 290. This could lead to an undesirable dilution of the sample in sample feeder 290. Port 241 can be connected to a container to collect the fluid.

Furthermore, in the first switching position of the pump supply switching valve 240, a flushing can take place, whereby a fluid, preferably a third fluid, is pumped into the sample feed 290 via ports 245 and 244.

16 describes another combination of the switching positions of the pump supply switching valve 240 and the injection valve 250.

As in 13 As described, the addition unit 249 comprises an injection valve 250 and a sample loop 251, wherein the injection valve 250 comprises eight ports (252, 253, 254, 255, 256, 257, 258, 259). Furthermore, in 16 A pump supply switching valve 240 with eight ports (241, 242, 243, 244, 245, 246, 247, 248) is shown, which is connected to other components, such as a third pump 236, a liquid reservoir 237 for a third fluid, a system 280 for rinsing a sample feeder 290, and a sample feeder 290. These components have been described in more detail previously, with identical reference numerals representing the same components, so that on 13 Reference is made to the description of these components.

In the 16 In the position combination shown, the pump supply switching valve 240 is in the second switching position, with the inlet line of the third pump 236 connected to a sample loop port 259 of the addition unit 249. The injection valve 250 of the addition unit 249 is switched in a second switching position, with the high-pressure ports (253, 254) for supplying and discharging high-pressure fluid connected to the two sample loop ports (252, 255), with port 253 connected to port 252 and port 254 to port 255.

In the switching position of injection valve 250, port 252 is connected to port 253 and port 255 to port 254. Furthermore, port 259 is connected to port 258 and port 257 to port 256. In this switching position of the pump supply switching valve 240, ports 241 and 242 are connected. Furthermore, port 243 is connected to 244, port 247 to port 248, and port 246 to port 245. Ports 242, 258, and 257 are closed.

It should be noted here that in this 16 In the presented position combination of the switching positions of both valves, each with eight ports, the third pump 236 is switched off because port 258 is closed. Therefore, after a short time, it is usually from the 15 The illustrated position combination of the switching positions of both valves, which is particularly useful for releasing a fluid located in the sample loop 251 into the 16 The presented combination of switching positions of both valves is activated, preferably in a coordinated manner. The third pump 236 is also switched off in this process.

The use of an eight-port injection valve leads to surprising improvements. This applies particularly to the yield of purified substances and the purity of the purified substances. It should be noted that in the 13 the presented combination of switching positions of both valves in the space between the The probe is present in the line provided for ports 243 and 256, which is transferred to the sample loop 251. In the 3 In the situation described, port 56 of the injection valve 51 is connected to port 48 of the pump supply line switching valve 40, with a third fluid present in the line between these two ports. This fluid is introduced into the sample loop 51 by injection and, during loading, is transferred from the sample loop 51 into the line section between ports 56 and 48. Since in the 3 In the presented combination of switching positions of both valves, the pipe section between port 43 and port 55 is connected to the pipe section between port 56 and port 48. Diffusion from both pipe sections can lead to dilution of the sample located in the pipe between port 43 and port 55. Furthermore, diffusion processes can introduce sample into the pipe section between port 56 and port 48. This fluid is unintentionally deposited onto the chromatography column when sample loop 51 is loaded. This can lead to these unintentionally deposited substances being washed off the chromatography column at an undefined time, potentially resulting in contamination.

It is clear that this point is of minor importance for many applications, so no effects are noticeable in many chromatographic processes. This is especially true if an identical sample is always applied, which is to be purified in smaller portions over several chromatographic runs. Furthermore, diffusion depends on the cross-sectional area of the lines or ports, which are often small, and on the duration of the chromatography. However, unexpected advantages can be achieved in very large-scale chromatographic processes.

In the 16 The presented combination of switching positions of both valves is the line between port 243 and port 256 from the line between port 259 and port 248. This ensures that no cross-contamination occurs when applying different samples or that a sample located in the line between port 243 and port 256 is not diluted.

The features of the invention disclosed in the preceding description, as well as in the claims, figures and embodiments, can be essential for the realization of the invention in its various embodiments, both individually and in any combination.

QUOTES INCLUDED IN THE DESCRIPTION

This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions.

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Claims (33)

A chromatography system comprising a first pump, which is connectable to or connected with a liquid reservoir for a first fluid, and a second pump, which is connectable to or connected with a liquid reservoir for a second fluid, wherein the pump outlet lines of the first pump and the second pump are connected by a connector, and a chromatography column is provided downstream of this connector in the direction of flow, and an injection unit is provided upstream of the chromatography column in the direction of flow, characterized in that the injection unit comprises a sample loop and an injection valve, wherein the injection valve has at least two sample loop ports and two high-pressure ports for supplying and discharging high-pressure fluid, as well as two sample loading ports for loading the sample loop, wherein the sample loop is connectable to or connected with the two sample loop ports of the injection valve, and a third pump is provided, the outlet line of which is connected to a high-pressure port of the injection valve, and the inlet line of the third pump is connected via a The pump supply line switching valve is switchable, wherein in a first switching position of the pump supply line switching valve the inlet line of the third pump can be connected to a liquid reservoir for a third fluid and in a second switching position of the pump supply line switching valve the inlet line of the third pump can be connected to a sample loading port of the addition unit. Chromatography system according to Claim 1 , characterized in that the third pump is a stepper motor pump. Chromatography system according to Claim 1 or 2 , characterized in that the addition unit is provided downstream of the connecting piece, viewed in the direction of flow. Chromatography system according to at least one of the preceding claims, characterized in that the pump supply switching valve and the injection valve can be switched in a coordinated manner. Chromatography system according to at least one of the preceding claims, characterized in that in a first switching position of the pump supply line switching valve the inlet line of the third pump is connected to a liquid reservoir for a third fluid and the injection valve of the addition unit is switched in a first switching position, wherein the two high-pressure ports for supplying and discharging fluid under high pressure are connected to each other and the sample loading ports for loading the sample loop are connected to the two sample loop ports. Chromatography system according to at least one of the preceding claims, characterized in that in a second switching position of the pump supply line switching valve the inlet line of the third pump is connected to a sample loading port of the addition unit and the injection valve of the addition unit is switched in a first switching position, wherein the sample loading ports for loading the sample loop are connected to the two sample loop ports. Chromatography system according to at least one of the preceding claims, characterized in that in a first switching position of the pump supply line switching valve the inlet line of the third pump is connected to a liquid reservoir for a third fluid and the injection valve of the addition unit is switched in a second switching position, wherein the two high-pressure ports for supplying and discharging fluid under high pressure are connected to the two sample loop ports. Chromatography system according to at least one of the preceding claims, characterized in that a mixer is provided between the connecting piece and the addition unit. Chromatography system according to at least one of the preceding claims, characterized in that the chromatography system is controllable via a chromatography system control system. Chromatography system according to at least one of the preceding claims, characterized in that a second connecting piece is provided which, viewed in the direction of flow, is located after the first connecting piece and before the chromatography column, wherein the second connecting piece is connected to the first connecting piece and the chromatography column via a high-pressure port for supplying and removing high-pressure fluid from the injection valve. Chromatography system according to Claim 10 , characterized in that a check valve is provided between the high-pressure port for supplying and discharging high-pressure fluid of the injection valve and the second connecting piece. Chromatography system according to at least one of the preceding claims, characterized in that the pump supply line switching valve has at least four ports, wherein one port is connected to the inlet line of the third pump, one port is connected to a sample loading port for loading the sample loop of the injection valve, one port is connected to a liquid reservoir for a third fluid and one port serves for pressure relief. Chromatography system according to Claim 12 , characterized in that in a first switching position of the pump supply line switching valve the inlet line of the third pump is connected to a liquid reservoir for a third fluid and a port connected to a sample loading port for loading the sample loop of the injection valve is connected to the port used for depressurization. Chromatography system according to at least one of the preceding claims, characterized in that the pump supply line switching valve has at least 6 ports, wherein one port is connected to the inlet line of the third pump, two ports are connected to two sample loading ports for loading the sample loop of the injection valve, one port is connected to a liquid reservoir for a third fluid, one port is connected to a sample container and/or a sample feeder, and one port serves for pressure relief. Chromatography system according to Claim 14 , characterized in that in a first switching position of the pump supply line switching valve the inlet line of the third pump is connected to a liquid reservoir for a third fluid and a port connected to a sample loading port for loading the sample loop of the injection valve is connected to the port used for depressurization. Chromatography system according to Claim 14 or 15 , characterized in that in a second switching position of the pump supply line switching valve the inlet line of the third pump is connected to a sample loading port of the addition unit and the port which is connected to a sample container is connected to a port which is connected to a sample loading port for loading the sample loop of the injection valve. Chromatography system according to at least one of the preceding claims, characterized in that the injection valve comprises eight ports, wherein two ports are sample loop ports, two ports are high-pressure ports for supplying and discharging high-pressure fluid, two sample loading ports are for loading the sample loop and two sealed ports. Chromatography system according to Claim 17 , characterized in that in a first switching position of the injection valve the two high-pressure ports for supplying and discharging fluid under high pressure are connected to each other and the two sample loading ports for loading the sample loop are connected to the two sample loop ports and the two closed ports are connected to each other. Chromatography system according to Claim 17 or 18 , characterized in that in a second switching position of the injection valve two high-pressure ports for supplying and discharging fluid under high pressure are connected to the two sample loop ports and the two sample loading ports for loading the sample loop are connected to the two closed ports. A chromatography system comprising a first pump, which is connectable to or connected with a liquid reservoir for a first fluid, and a second pump, which is connectable to or connected with a liquid reservoir for a second fluid, wherein the pump outlet lines of the first pump and the second pump are connected by a connector, and a chromatography column is provided downstream of this connector in the direction of flow, and an injection unit is provided upstream of the chromatography column in the direction of flow, wherein the chromatography system comprises a fraction collection device provided downstream of the chromatography column in the direction of flow, characterized in that the fraction collection device comprises a first fraction switching valve and a second fraction switching valve, wherein the first fraction switching valve has at least four ports, wherein one port of the first fraction switching valve is connected to the outlet line of the chromatography column, one port of the first fraction switching valve is connected to the outlet line of a rinsing pump, and one port of the first fraction switching valve is connected to a port of the second The fraction switching valve is connected, and one port of the first fraction switching valve is connected to a fraction collector or a waste collection container. Chromatography system according to Claim 20 , characterized in that in a first switching position of the first fraction switching valve the outlet line of the chromatography column is connected to a fraction collector or a waste collection vessel is connected and the outlet line of a flushing pump is connected to a port of the second fraction switching valve. Chromatography system according to Claim 20 or 21 , characterized in that in a second switching position of the first fraction switching valve the outlet line of the chromatography column is connected to a port of the second fraction switching valve. Chromatography system according to at least one of the preceding Claims 20 until 22 , characterized in that the first fraction switching valve has at least five ports, the fifth port being connected to a port of the in Claim 1 is connected to the pump supply line switching valve shown. Chromatography system according to Claim 23 , characterized in that in a second switching position of the first fraction switching valve the outlet line of the chromatography column is connected to a port of the second fraction switching valve and the outlet line of a rinsing pump is connected to a port of the pump supply line switching valve. Chromatography system according to at least one of the preceding claims, characterized in that the chromatography system is designed as an SFC system, wherein the chromatography system comprises a chromatography column and, viewed in the direction of flow, at least one back pressure regulator. Methods for carrying out chromatography comprising the use of a chromatography system according to at least one of the preceding Claims 1 until 25 . Procedure according to Claim 26 , characterized in that the liquid reservoir for a first fluid contains a first solvent which is liquid under normal conditions, and the liquid reservoir for a second fluid contains a gaseous solvent which is gaseous under normal conditions. Procedure according to Claim 26 or 27 , characterized in that , during the loading of the sample loop, the pump supply switching valve is switched to the second switching position and the injection valve of the addition unit is switched to a second switching position, wherein the sample loading ports for loading the sample loop are connected to the two sample loop ports, so that the third pump draws the sample to be separated from a sample storage container into the sample loop. Procedure according to at least one of the Claims 26 until 28 , characterized in that when a sample to be separated is applied to the chromatography column, the pump supply switching valve is switched to the first switching position and the injection valve of the addition unit is switched to a second switching position, wherein the sample loading ports for loading the sample loop are connected to the two high-pressure ports for supplying and discharging fluid under high pressure, so that the third pump pumps the sample to be separated from the sample loop to the chromatography column with a third solvent. Procedure according to at least one of the Claims 26 until 29 , characterized in that gradient chromatography is performed, wherein the proportion of first fluid at the beginning of the chromatography is in the range of 0 to 10 vol% and this proportion of first fluid is increased, wherein the pump supply switching valve is switched to the first switching position and the injection valve of the addition unit is switched to a first switching position, wherein the two high-pressure ports for supplying and discharging fluid under high pressure are connected to each other, so that the third pump provides at least 50 vol% of the first fluid at the beginning of the chromatography to form the desired fluid mixture comprising a first and a second fluid. Procedure according to at least one of the Claims 26 until 30 , characterized in that when collecting valuable fractions of a sample, the first fraction switching valve is switched to the second switching position and the outlet line of the chromatography column is connected to a port of the second fraction switching valve. Procedure according to at least one of the Claims 26 until 31 , characterized in that when collecting valuable fractions of a sample, the first fraction switching valve is switched to the first switching position and the outlet line of a rinsing pump is connected to a port of the second fraction switching valve, wherein the outlet line of the chromatography column is connected to a fraction collector. Conversion kit for converting a high-performance liquid chromatography system into a chromatography system according to at least one of the preceding Claims 1 until 25 , characterized in that the kit includes at least one gas liquid separator and at least one pump supply line switching valve.