DE102011005003A1 - Plant for the conversion of alkylene oxides - Google Patents

Abstract

The present invention relates to a system for converting alkylene oxides, comprising at least one reactor vessel, at least one educt feed line, at least one circulation line with a pump and an injector mixing nozzle, the gas feed of the injector mixing nozzle being connected to the gas space of the reactor vessel via a gas line, which is connected to at least one feed line. Another aspect of the present invention is a process for the preparation of alkylene oxide derivatives.

Description

The present invention relates to a plant for the reaction of alkylene oxides. In addition, the present invention describes processes for the preparation of alkylene oxide derivatives.

Derivatives of alkylene oxides, in particular of ethylene oxide or propylene oxide, are widely known in the art, these compounds being used, for example, as nonionic surfactants or as monomers having dispersing properties. Among the nonionic surfactants include fatty alcohols which have been reacted with ethylene or propylene oxide. Monomers with dispersing properties are in particular (meth) acrylates with glycol units.

Accordingly, many methods are known for obtaining the alkylene oxide derivatives set forth above. These are among other things in the pamphlets JP 2008143814 and JP 2008127302 described.

The known processes and equipment for carrying them out lead to acceptable yields and qualities of the desired products. Due to the economic importance of the alkylene oxide derivatives to be produced, there is a continuing need to further improve the economics of the processes. In doing so, other peculiarities of the processes for the preparation of these products should not be adversely affected. Accordingly, inter alia, the purity as well as the yield of the alkylene oxide derivatives should not be compromised by a process improvement in economic terms.

Furthermore, a plant for carrying out the said processes should be provided, by means of which the process can be carried out in a particularly simple, safe and cost-effective manner.

Furthermore, reactors for the reaction of gases with liquid starting materials from the document EP 0070797 in which the reaction mixture is circulated and the gas is introduced into the reaction mixture via an injector mixing nozzle. The injector mixing nozzle is designed such that the gas in the reactor vessel is sucked in above the reaction mixture and brought into contact therewith. A gas line between the reactor chamber and injector mixing nozzle is not indicated, and this complex construction is not necessary for the stated reaction. The reaction of alkylene oxides with this plant is not described. Furthermore, an introduction of a liquid starting material in the gas supply of the injector mixing nozzle is not set forth.

In view of the prior art, it was therefore an object of the present invention to provide a process for the preparation of alkylene oxide derivatives, which is particularly economical.

Moreover, it was an object of the present invention to provide processes for the preparation of alkylene oxide derivatives, which can be carried out easily and safely. In this case, the product should preferably be obtained in high yields and, overall, with low energy consumption.

Another object of the invention was to provide a method in which an alkylene oxide derivative can be obtained very selectively. Furthermore, the method should provide as constant as possible product quality.

Furthermore, a plant for the reaction of alkylene oxides should be made available, with which the methods set out above can be carried out easily and inexpensively. Here, the system should have a simple structure. Furthermore, a long continuous operation of the system should be made possible without the operation of the system must be interrupted. Furthermore, the system should be able to be easily cleaned.

These and other objects which are not explicitly mentioned, but which are readily derivable or deducible from the contexts discussed hereinbelow, are solved by a plant for the reaction of alkylene oxides with all features of patent claim 1. Advantageous modifications of the systems according to the invention are described in the claims 1 to 3 backed dependent claims. With regard to a process for the preparation of alkylene oxide derivatives, claim 5 provides a solution to the underlying objects.

The present invention accordingly relates to a plant for the reaction of alkylene oxides, comprising at least one reactor vessel, at least one educt feed, at least one Circulation line with a pump and an injector mixing nozzle, which is characterized in that the gas supply of the injector mixing nozzle is connected to the gas space of the reactor vessel via a gas line which is connected to at least one educt feed line.

This makes it possible to provide an installation and a process for the preparation of alkylene oxide derivatives in an unpredictable manner, with which the said products can be obtained particularly economically.

An inventive method for the production of alkylene oxide derivatives can be carried out easily and safely. Here, the products are obtained in high yields and, overall, with low energy consumption. Thus, the proportion of by-products can be reduced, the use of alkylene oxide reduced and the reaction time can be reduced. In this context, it should be noted that the process according to the invention leads to particularly small amounts of undesirable and critical by-products, for example to di (meth) acrylates.

In addition, the alkylene oxide derivatives can be obtained very selectively, the process providing a comparatively constant product quality.

Furthermore, a plant for the reaction of alkylene oxides is provided with which the methods set out above can be carried out simply and inexpensively. Here, the system has a comparatively simple structure. Furthermore, a long continuous operation of the system is made possible without the operation of the system must be interrupted. Furthermore, the system can be cleaned easily.

The plant for the reaction of alkylene oxides comprises at least one reactor vessel, at least one educt feed line and at least one circulation line with a pump. These components of the system according to the invention are known from the prior art, in which connection reference is made inter alia to the documents set forth in the introductory part of the present application. Furthermore, particularly suitable reactors and pumps are inter alia in Dubbel - Paperback for Mechanical Engineering. 22nd edition. Springer, Berlin 2007. ISBN 978-3-540-49714-1 and VDI-Wärmeatlas VDI-Wärmeatlas VDI Gesellschaft (ed.) 10., edit. u. ext. Ed., 2006, ISBN: 978-3-540-25504-8 described.

Advantageously, the reactor vessel can be designed as a pressure reactor, with preferred reactor vessels being designed to be temperature-controllable and, for example, having half-pipe coils for cooling. Preferred pumps for circulating the reaction mixture include centrifugal pumps, which preferably include an open barrel, and side channel machines.

The plants according to the invention have a recirculation line, the reaction mixture being conducted in the same. Accordingly, the plant of the present invention may be considered as a loop reactor, also called loop reactor or loop reactor. In the recirculation line, at least one heat exchanger may preferably be provided. Suitable heat exchangers are inter alia in Dubbel - Paperback for Mechanical Engineering. 22nd edition. Springer, Berlin 2007. ISBN 978-3-540-49714-1 and VDI-Wärmeatlas VDI-Wärmeatlas VDI Gesellschaft (ed.) 10., edit. u. ext. Ed., 2006, ISBN: 978-3-540-25504-8 explained.

Surprising advantages can be obtained, inter alia, that the heat exchanger is designed as a tube bundle heat exchanger.

Preferably, the reactor may have, in addition to the injector mixing nozzle, a stirrer which may be provided, for example, in the reactor vessel.

V1

= Volumenstrom Sauggas aus Reaktor;

V2

= Volumenstrom Treibmedium

Essential to the invention is the use of an injector mixing nozzle. The design and geometry of preferred injector mixing nozzles are designed so that a relatively high suction ratio can be achieved. The suction ratio (SVH) is defined as SVH = V1 [m ³ / h] / V2 [m ³ / h];

V1

= Volume flow of suction gas from reactor;

V2

= Volume flow of propellant

For a given volume flow of the driving medium, which is generated for example by the pump in the liquid circuit, injector mixing nozzles with high suction ratio show a strong volume flow of the gas, which is withdrawn from the gas space of the reactor.

In particular, injector mixing nozzles, with which a suction ratio in the range of 0.5 to 20, in particular 1 to 10 and particularly preferably in the range of 2 to 7, can be achieved, show surprising advantages.

The injector mixing nozzle has a gas supply and a supply for a liquid flow. Furthermore, the gas supply of the injector-mixing nozzle is connected to the gas space of the reactor vessel via a gas line which is connected to at least one Eduktzuleitung so that a gas can be sucked through the liquid stream via the gas supply of the injector mixing nozzle from the reactor vessel. Of particular advantage may be a throttle valve, which is provided in the gas line, which connects the gas space of the reactor with the injector mixing nozzle. In this way, in particular, the gas flow in the gas line can be adjusted independently of the circuit of the liquid flow to the injector mixing nozzle.

Furthermore, at least one educt feed line is provided in the gas line to the injector mixing nozzle. The feed point of the educt feed line into the gas line to the injector mixing nozzle is preferably designed such that a liquid can be introduced into the gas line to the injector mixing nozzle. Accordingly, a pressure-maintaining valve can be provided in the educt feed line via which an educt can be introduced into the gas line to the injector mixing nozzle. Furthermore, the liquid educt which can be introduced into the reactor can be metered via a pump from a storage container into the gas line to the injector mixing nozzle.

The feed point of the reactant feed line into the gas line to the injector mixing nozzle can advantageously be selected such that the feedstock introduced liquid into the gas feed line travels a distance of at least 50 mm, more preferably at least 100 mm, into the gas flow of the gas feed line before contact with the recycle stream. Preferably, this distance is at most 2000 mm, more preferably at most 1000 mm.

Of particular interest is, inter alia, a plant which is designed as a feedbatch plant. A feedbatch plant allows the supply of a portion of the reactants during the implementation of the reaction, during which reaction only a negligible portion of the products obtained is discharged from the reactor. In particular, samples of the reaction mixture which serve to analyze the progress of the reaction can be regarded as an insignificant part. Preferably, the plant can be designed so that at least one of the starting materials is substantially completely charged, whereas another starting material to preferably at least 60 wt .-%, preferably at least 80 wt .-% and particularly preferably at least 95 wt .-% on the provided in the gas supply of the injector mixing nozzle Eduktzuleitung can be initiated. For example, preferably at least 90% by weight, particularly preferably at least 95% by weight of an alcohol or an acid, for example (meth) acrylic acid, are initially charged in the reactor vessel, whereas preferably at least 60% by weight, preferably at least 80% by weight. % and more preferably at least 95 wt .-% of usable alkylene oxides can be introduced via the provided in the gas line for supplying gas to the injector mixing educt feedstock.

The geometries of the lines, in particular the educt feed line, the gas line and the circulation stream are preferably selected such that the flow rate in the educt feed line, the gas line and / or the circulation stream is in the range from 0.2 m / s to 20 m / s.

An inventive system is used in particular for the production of alkylene oxide derivatives. Derivatives of alkylene oxide are in particular compounds which can be obtained by reacting alkylene oxides. The preferred derivatives of alkylene oxide include in particular esters and ethers which have one or more alkylene glycol units.

Alkylene oxides are known in the art, these compounds can be obtained in particular by epoxidation of alkenes. Among the preferred alkylene oxides include ethylene oxide, propylene oxide and / or butylene oxide. These compounds may be used singly or as mixtures of two or more. For the preparation of particularly preferred derivatives of alkylene oxides, the composition of the alkylene oxides used can be varied in order to obtain, for example, block copolymers. In particular, preferred block copolymers can be obtained by polymerization of ethylene oxide and propylene oxide.

Of particular interest are, in particular, processes in which at least one alkylene oxide in the liquid phase is fed into the educt feed line of the reaction mixture, which is provided in the gas feed of the injector mixing nozzle.

The addition time of the alkylene oxide is preferably in the range of 10 minutes to 48 hours, more preferably in the range of 30 minutes to 24 hours.

Furthermore, preference is given to processes in which the metering ratio is in the range from 5 to 500, in particular in the range from 20 to 200 and particularly preferably in the range from 40 to 80. The metering ratio (DV) describes the weight ratio of the stream of alkylene oxide addition (metered amount) to circulation stream (circulation amount), so that DV = M1 [kg / h] / M2 [kg / h] with M1 = circulation rates; M2 = dosing quantity.

Preferably, the charge and the amount of starting material added may be selected so that the level of the reactor vessel is at the end of the reaction below the outlet of the injector mixing nozzle.

Also of particular interest are systems which are designed such that the reactor residence time (RWZ) is in the range of preferably 1 to 60 minutes, in particular 2 to 20 minutes and particularly preferably 5 to 15 minutes. Processes with these reactor residence times are particularly preferred.

The reactor residence time (RWZ) is defined as:
RWZ [h] = V _R [m ³ ] / V _u [m ³ / h]; V _R = reactor volume; V _u Umwälzvolumenstrom

According to a particular aspect of the present invention, in particular derivatives of (meth) acrylic acid can be formed. The term (meth) acrylic acid includes methacrylic acid, acrylic acid and mixtures thereof.

Advantageously, the process according to the invention can be used in particular for the preparation of glycol esters of (meth) acrylic acid. These include, for example, hydroxyalkyl (meth) acrylates such as 2-hydroxyethyl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl methacrylate, 2-hydroxypropyl acrylate, 3-hydroxypropyl methacrylate, 3-hydroxypropyl acrylate, hydroxybutyl methacrylate and hydroxybutyl acrylate.

Particularly preferred are in particular processes for the preparation of polyalkylene glycol mono (meth) acrylates. In the context of the present invention, the term polyalkylene glycol mono (meth) acrylate is understood in particular to mean a monoester of (meth) acrylic acid which is derived from an ether, in particular a polyether.

The ether compounds from which the (meth) acrylic acid ester is derived include, in particular, poly-C ₂ -C ₄ -alkylene glycol compounds which are also known in various ways as poly-C ₂ -C ₄ -alkylene oxides or poly (oxy-C ₂ -C ₄ -) alkylene) compounds. These ethers usually have at least 2, often at least 4 and especially at least 5 and usually not more than 500, often not more than 400, z. B. 2 to 100 and especially 3 to 50 repeat units derived from C ₂ -C ₄ alkylene glycols. These compounds can be linear or branched.

worin R Wasserstoff oder eine Methylgruppe, n die Anzahl der Wiederholungseinheiten angibt und in der Regel für eine Zahl im Bereich von 2 bis 100, insbesondere im Bereich von 3 bis 50, besonders bevorzugt im Bereich von 4 bis 15 und ganz besonderes bevorzugt im Bereich von 5 bis 10 steht, A für C₂-C₄-Alkylen wie 1,2-Ethandiyl, 1,3-Propandiyl, 1,2-Propandiyl, 1,2-Butandiyl oder 1,4-Butandiyl und R¹ für Wasserstoff steht.Preferred polyalkylene glycol mono (meth) acrylates can be described by the general formula (I)

wherein R is hydrogen or a methyl group, n indicates the number of repeating units and usually for a number in the range of 2 to 100, in particular in the range of 3 to 50, particularly preferably in the range of 4 to 15 and very particularly preferably in the range of 5 to 10, A is C ₂ -C ₄ -alkylene, such as 1,2-ethanediyl, 1,3-propanediyl, 1,2-propanediyl, 1,2-butanediyl or 1,4-butanediyl and R ^{1 is} hydrogen ,

Of particular interest are, in particular, polyalkylene glycol mono (meth) acrylates which preferably have a number average molecular weight in the range from 200 to 6000 g / mol, more preferably in the range from 500 to 5000 g / mol, determined by their hydroxyl number.

According to a particular aspect of the present invention, a polyethylene mono (meth) acrylate may preferably be prepared which comprises on average from about 3 to 10, more preferably from about 4 to 6 units derived from ethylene oxide. Particularly preferably, the radical R ¹ in these compounds is hydrogen, A is exclusively 1,2-ethanediyl and n is an integer in the range from 3 to 10, particularly preferably 4 to 6.

According to a further embodiment of the present invention, it is possible with preference to prepare a polypropylene glycol mono (meth) acrylate which comprises on average from about 3 to 10, particularly preferably about 4 to 6, units derived from propylene oxide. Particularly preferably, the radical R ¹ in these compounds is hydrogen, A is 1,2-propanediyl and n is an integer in the range from 3 to 10, particularly preferably 4 to 6.

Accordingly, (meth) acrylic acid and / or hydroxyalkyl (meth) acrylates can be used in particular as starting materials. In particular, polyalkylene glycol mono (meth) acrylates can be obtained by reacting (meth) acrylic acid and / or hydroxyalkyl (meth) acrylates with at least one alkylene oxide. For the preparation of hydroxyalkyl (meth) acrylates having an alkylene glycol group in the molecule, (meth) acrylic acid is generally used.

Depending on the nature of the alkylene oxide derivative of (meth) acrylic acid to be prepared, the molar ratio of alkylene oxide to (meth) acrylic acid and / or hydroxyalkyl (meth) acrylate can be within a wide range. When preparing products having an alkylene glycol group in the molecule, surprising advantages can be obtained by the molar ratio of alkylene oxide to (meth) acrylic acid in the range of 0.95: 1 to 1.5: 1, more preferably in the range of 1: 1 to 1.1: 1. These values relate to the total amount of educts added, since the alkylene oxide is preferably introduced into the reaction mixture via the educt feed line, which is provided in the gas feed of the injector mixing nozzle.

Surprising advantages in the preparation of derivatives having two or more alkylene glycol groups in the molecule is the molar ratio of alkylene oxide to (meth) acrylic acid and / or hydroxyalkyl (meth) acrylate for the desired product, wherein the molar ratio of alkylene oxide to (meth ) acrylic acid and / or hydroxyalkyl (meth) acrylate preferably in the range of 1: 1 to 1000: 1, more preferably 2: 1 to 100: 1, more preferably 3: 1 to 10: 1 can lie.

The preparation of ethylenically unsaturated alkylene oxide derivatives, which are preferably derived from (meth) acrylic acid, can be carried out in the presence of polymerization inhibitors, and these can in many cases already be used for the preparation of the unsaturated compounds. Particularly preferred polymerization inhibitors include phenolic compounds such as hydroquinones, hydroquinone ethers such as hydroquinone monomethyl ether, tert-butylhydroquinone, 2,6-di-tert-butylhydroquinone, 2,5-di-tert-butylhydroquinone, 2,4-dimethyl-6 tert-butylphenol or di-tert-butylcatechol; p-phenylenediamines, such as N, N'-diphenyl-p-phenylenediamine, N, N'-di-2-naphthyl-p-phenylenediamine, N, N'-di-p-tolyl-p-phenylenediamine, N- 1,3-dimethylbutyl-N'-phenyl-p-phenylenediamine and N-1,4-dimethylpentyl-N'-phenyl-p-phenylenediamine; Amines, such as thiodiphenylamine and phenothiazine; Copper dialkyldithiocarbamates such as copper dimethyldithiocarbamates, copper diethyldithiocarbamates and copper dibutyldithiocarbamates; Nitroso compounds such as nitrosodiphenylamine, isoamyl nitrite, N-nitrosocyclohexylhydroxylamine, N-nitroso-N-phenyl-N-hydroxylamine and their salts; and N-oxyl compounds such as 2,2,4,4-tetramethylazetidine-1-oxyl, 2,2-dimethyl-4,4-dipropylazetidin-1-oxyl, 2,2,5,5-tetramethylpyrrolidin-1 oxyl, 2,2,5,5-tetramethyl-3-oxopyrrolidin-1-oxyl, 2,2,6,6-tetramethylpiperidine-1-oxyl, 4-hydroxy-2,2,6,6-tetramethylpiperidine-1 oxyl, 6-aza-7,7-dimethylspiro [4,5] decane-6-oxyl, 2,2,6,6-tetramethyl-4-acetoxypiperidine-1-oxyl and 2,2,6,6-tetramethyl 4-benzoyloxypiperidine-1-oxyl; Methylene blue, nigrosine base BA, 1,4-benzoquinone, hindered phenols, for example 2,4-dimethyl-6-tert-butylphenol and / or tocopherol compounds, preferably α-tocopherol.

The polymerization inhibitors may be used singly or in the form of mixtures and are generally available commercially. For further details on the usual specialist literature, in particular on the Römpp-Lexikon Chemistry; Publisher: J. Falbe, M. Regitz; Stuttgart, New York; 10th edition (1996); Keyword "antioxidants" and references cited at this point.

Surprising advantages can be achieved, in particular, by reaction mixtures which preferably contain from 1 to 5000 ppm, particularly preferably from 5 to 1000 ppm and very particularly preferably from 10 to 100 ppm of polymerization inhibitor.

The reaction temperature in the preparation of alkylene oxide derivatives of (meth) acrylic acid is preferably in the range of 50 ° C to 100 ° C, more preferably in the range of 60 to 80 ° C. The absolute pressure in the reactor vessel of this reaction may preferably be in the range from 0 to 6 bar, in particular in the range from 1 to 5 bar, particularly preferably in the range from 2 to 3 bar.

For the implementation of catalysts are preferably used. Preferred catalysts are inter alia in EP-A-1 231 204 , filed on 31.01.2002 at the European Patent Office with the application number EP 02002363.6 wherein the disclosure of this document, in particular the catalysts and methods for producing hydroxyalkyl (meth) acrylates described therein, are incorporated into the present application for the purpose of disclosure.

According to a further embodiment, alcohols can be used as starting materials for the preparation of alkylene oxide derivatives. Among the preferred alcohols include methanol, ethanol and propanol, although also ether derivatives of these alcohols can be used, such as methyl triglycol (MTG).

The reaction temperature in the production of alkylene oxide ethers is preferably in the range of 50 to 200 ° C, more preferably in the range of 120 ° C to 150 ° C. The absolute pressure in the reactor vessel of this reaction may preferably be in the range from 0 to 6 bar, more preferably in the range from 2 to 3 bar.

Preferably, the reaction of alcohols with alkylene oxides can be carried out under catalysis. Preferred catalysts include, but are not limited to, strong bases such as alcoholates, oxides and hydroxides of alkali metals. These include, for example, NaOH, KOH, NaOCH ₃ , and NaOC ₂ H ₅ .

Depending on the nature of the ether derivatives of the alkylene oxides to be prepared, the molar ratio of alkylene oxide to alcohol can be within a wide range. When producing products having an alkylene glycol group in the molecule, surprising advantages can be achieved by the molar ratio of alkylene oxide to alcohol in the range from 1: 1 to 1000: 1, particularly preferably in the range from 5: 1 to 100: 1 lies. These values relate to the total amount of educts added, since the alkylene oxide is preferably introduced into the reaction mixture via the educt feed line, which is provided in the gas feed of the injector mixing nozzle.

A preferred embodiment of a plant for carrying out the method set forth above is in 1 explained.

1 shows a plant for the conversion of alkylene oxides 1 holding a reactor vessel 2 , an educt feed line 3 , a circulation line 4 with a pump 5 and an injector mixing nozzle 6 wherein the gas supply of the injector mixing nozzle 6 with the gas space of the reactor vessel via a gas line 7 connected is. Essential to the invention is that the gas line 7 with at least one educt feed 3 communicates.

The reactor vessel 2 is preferably designed as a pressure reactor and can be a temperature, for example, a jacket cooling 8th exhibit. Furthermore, surprising advantages can be achieved with a stirrer 9 be achieved, which is provided in the reactor vessel.

The reaction mixture is circulated through a recirculation line 4 led, so that the same from the reactor vessel 2 via a pump 5 to the injector mixing nozzle 6 is pumped. For the dissipation of heat, the circulation line 4 with a heat exchanger 10 be equipped. By introducing liquid into the corresponding supply line of the injector mixing nozzle 6 may be a negative pressure in the gas supply of the injector mixing nozzle 6 be generated, allowing gas from the gas space of the reactor vessel 2 over the gas line 7 is deducted. For controlling the gas flow or the negative pressure in the gas line 7 can be a throttle valve 11 be provided in the same.

In the gas line 6 leads a feedstock 3 , preferably for introducing a liquid into the gas line 7 suitable is. Preferably, therefore, the educt feed 3 with a pressure relief valve 12 be equipped. Furthermore, for metering of the educt, which is preferably present in the liquid phase in the educt feed 3 a pump 13 be provided. The educt feed line 3 preferably connects an educt reservoir 14 with the gas line 7 , Between the connection point of the educt feed line 3 with the gas line 7 and the injector mixing nozzle 6 there is a mixing section 15 ,

2 shows a preferred embodiment of an injector-mixing nozzle 6 in detail. This preferred injector mixing nozzle 6 is with the circulation line 4 connected, so that a recirculation flow can be formed. By supplying a liquid under pressure in this supply line 4 and the derivative thereof via the nozzle exit 61 is in the nozzle body 62 generates a negative pressure, which is used to suck in a gas stream via the gas supply line 7 can be used. In the gas supply line 7 leads a feedstock 3 that with a pressure-holding valve 12 Is provided. The feed point of the educt feed line 3 with the pressure-holding valve 12 is preferably chosen so that a mixing section 15 between entry point 63 and nozzle entry 64 is obtained.

Hereinafter, the present invention will be explained with reference to examples and comparative examples, without thereby limiting it.

example 1

In a plant according to 1 Methacrylic acid was reacted with ethylene oxide. For this purpose, 5300 kg (61.6 kmol) of methacrylic acid were added to the reactor vessel and treated with 12 kg (52.4 mol) of chromium acetate and 2.5 kg (20.1 mol) of HQME and heated to a temperature of 70 ° C. Subsequently, the mixture was passed through a pump in the injector mixing nozzle, wherein a circulating volume flow of about 70 m ³ / h was set. Subsequently, 2720 kg (61.7 kmol) of ethylene oxide were added via the educt feed line into the gas feed of the injector mixing nozzle. The dosage was chosen so that a reaction temperature of 70 ° C was not exceeded and was about 900 kg / h (20.4 kmol / h).

After the addition of the intended amount, the reaction mixture was recirculated for a further 5 hours at a temperature of 70 ° C.

The total reaction time of the reaction was 8 hours. The resulting reaction mixture was analyzed with the proportion of 2-hydroxyethyl methacrylate being about 95.4% as determined by GC-FID (gas chromatography combined with a flame ionization detector). The largest proportion of by-product was formed by diethylene glycol methacrylate at a level of about 3.60%. A particularly critical byproduct is ethylene glycol dimethacrylate with a proportion of about 0.11%.

Comparative Example 1

Example 1 was substantially repeated, with 2740 kg (62.2 kmol) of ethylene oxide added directly to the reactor vessel.

The dosage was chosen so that a reaction temperature of 70 ° C was not exceeded and was about 800 kg / h (20.4 kmol / h). The total reaction time of the reaction was 8.5 hours.

The resulting reaction mixture was analyzed with the proportion of 2-hydroxyethyl methacrylate being about 95.1% as determined by GC-FID (gas chromatography combined with a flame ionization detector). The largest proportion of by-product was formed by diethylene glycol methacrylate at a level of about 3.83%. A particularly critical byproduct is ethylene glycol dimethacrylate with a proportion of about 0.14%.

The experiments set out show that the inventive system reduces the consumption of alkylene oxide, minimizes the formation of critical byproducts, in particular of dimethacrylates, and reduces the reaction time.

Example 2

In a plant according to 1 hydroxypropyl methacrylate was reacted with propylene oxide. For this purpose, 577 kg (4 kmol) of hydroxypropyl methacrylate were added to the reactor vessel and treated with 13.4 kg of boron trifluoride-acetic acid complex and 750 g (6.04 mol) of HQME and heated to a temperature of 50 ° C. Subsequently, the mixture was passed through a pump in the injector mixing nozzle, wherein a circulating volume flow of about 10 m ³ / h was set. Subsequently, 976 kg (16.8 kmol) of propylene oxide were introduced via the educt feed line into the gas feed of the injector mixing nozzle. The metered amount was chosen so that a reaction overpressure of 3.5 bar was not exceeded and was about 120 kg / h (2.07 kmol / h).

After the addition of the intended amount, the reaction mixture was recirculated for a further 2 hours at a temperature of 50.degree.

The total reaction time of the reaction was 10 hours. The neutralization of the reaction mixture is then carried out at 70 ° C with the addition of 45.5 kg of sodium carbonate decahydrate. After the neutralization time of 4 hours, the reaction mixture was cooled and filtered. There are obtained about 1500 kg of polypropylene glycol monomethacrylate, which has an OH number of 133 mg KOH / g, which corresponds to a Propoxylierungsgrad of 5.3.

Example 3

In a plant according to 1 Methyltriglycol was reacted with ethylene oxide. To this end, 1300 kg (7.92 kmol) of methyltriglycol were added to the reactor vessel and treated with 40 kg (0.74 kmol) NaOCH ₃ and heated to a temperature of 125 ° C. Subsequently, the mixture was passed through a pump in the injector mixing nozzle, wherein a circulating volume flow of about 70 m ³ / h was set. Subsequently, 7630 kg (173.21 kmol) of ethylene oxide were added via the educt feed line into the gas feed of the injector mixing nozzle. The metered amount was chosen so that a reaction overpressure of 0.61 bar was not exceeded and was about 950 kg / h (21.57 kmol / h).

After the addition of the intended amount, the reaction mixture was recirculated for a further 2 hours at a temperature of 125 ° C.

The total reaction time of the reaction was 10 hours. About 6300 kg of methoxypolyethylene glycol compound are obtained, which has an OH number of 55 mg KOH / g, which corresponds to a molecular weight of 1018 g / mol.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• JP 2008143814 [0003]
• JP 2008127302 [0003]
• EP 0070797 [0006]
• EP 1231204A [0053]
• EP 02002363 [0053]

Cited non-patent literature

• Dubbel - Paperback for Mechanical Engineering. 22nd edition. Springer, Berlin 2007. ISBN 978-3-540-49714-1 [0017]
• VDI-Wärmeatlas VDI-Wärmeatlas VDI Gesellschaft (ed.) 10., edit. u. ext. Ed., 2006, ISBN: 978-3-540-25504-8 [0017]
• Dubbel - Paperback for Mechanical Engineering. 22nd edition. Springer, Berlin 2007. ISBN 978-3-540-49714-1 [0019]
• VDI-Wärmeatlas VDI-Wärmeatlas VDI Gesellschaft (ed.) 10., edit. u. ext. Ed., 2006, ISBN: 978-3-540-25504-8 [0019]
• Römpp-Lexikon Chemistry; Publisher: J. Falbe, M. Regitz; Stuttgart, New York; 10th edition (1996); Keyword "antioxidants" [0050]

Claims (15)

Plant for the conversion of alkylene oxides 1 comprising at least one reactor vessel 2 , at least one educt feed 3 , at least one circulation line 4 with a pump 5 and an injector mixing nozzle 6 , characterized in that the gas supply of the injector mixing nozzle 6 with the gas space of the reactor vessel 2 via a gas line 7 is connected, which with at least one Eduktzuleitung 3 connected is. Plant according to claim 1, characterized in that in the circulation line 4 at least one heat exchanger 10 is provided. Installation according to claim 1 or 2, characterized in that a pressure-holding valve 12 in the educt feed line 3 is provided. Plant according to at least one of the preceding claims, characterized in that in the reactor vessel 2 a stirrer is provided. Plant according to at least one of the preceding claims, characterized in that the injector mixing nozzle achieves a suction ratio in the range of 0.5 to 20. Process for the preparation of alkylene oxide derivatives, characterized in that a plant according to at least one of claims 1 to 5 is used for carrying out the process. A method according to claim 6, characterized in that at least one alkylene oxide is fed in the liquid phase in the feedstock of the reaction mixture, which is provided in the gas line to the injector mixing nozzle. A method according to any one of claims 6 or 7, characterized in that the method is carried out with a metering ratio in the range of 5 to 500. A method according to any one of claims 6 to 8, characterized in that the pressure at which the reaction takes place in the range of 1 to 5 bar. A method according to any one of claims 6 to 9, characterized in that ethylene oxide and / or propylene oxide is used as starting material. A method according to any one of claims 6 to 10, characterized in that (meth) acrylic acid and / or at least one hydroxyalkyl (meth) acrylate is used as starting material. A method according to claim 11, characterized in that the molar ratio of alkylene oxide to (meth) acrylic acid in the range of 1.1: 1 to 1: 1. A method according to claim 11, characterized in that the molar ratio of alkylene oxide to (meth) acrylic acid and / or hydroxyalkyl (meth) acrylate in the range of 2: 1 to 100: 1. A method according to any one of claims 6 to 10, characterized in that an alcohol is used as starting material. A method according to claim 14, characterized in that the molar ratio of alkylene oxide to alcohol in the range of 5: 1 to 100: 1.

Images