CN1023797C - Olefin Alcohol Process - Google Patents

Abstract

The invention discloses an alcohol preparation process for hydroformylating olefin with 9 to 15 carbon atoms to generate normal alcohol as a main product in one step. The whole process is divided into three sections, and the catalyst regeneration section is arranged before the reaction engineering, so that the concentration of active species of the cobalt-phosphine complex catalyst is improved, the reaction activity is improved, and the consumption quota of the catalyst and the cost for producing alcohol are reduced. Two thin film evaporators are used in series, so that the residence time of the catalyst at high temperature in vacuum is reduced.

Description

The present invention relates to a continuous process for the reaction of olefins with carbon monoxide and hydrogen to form alcohols, the so-called continuous process for the hydroformylation of olefins.

Olefin hydroformylation is a well-known process in which an olefin, usually a linear olefin, is reacted with carbon monoxide and hydrogen in the presence of a suitable catalyst to form an alcohol in one step as follows:

R ₁ and R ₂ generally represent a hydrogen atom or an alkyl group, and R ₂ is usually a hydrogen atom.

The raw olefins can also be mixed olefins, such as C9-C10, C11-C12, C13-C14, C15-C16, etc., or a mixture of olefins in which the olefin content is about 80% by weight. The use of this type of raw material can greatly reduce the cost of alcohol production and broadly expand the source of raw material olefins.

In order to realize the above-mentioned process, various implementation schemes and technical solutions have been proposed in terms of catalysts, reaction conditions, process and many other aspects, so as to achieve the purpose of obtaining alcohol from olefins economically, reasonably and conveniently.

The catalysts used at the beginning are transition metal carbonyl complexes without phosphine ligands, such as HCo(CO) ₄ and so on. The advantage of the technological process using this type of catalyst is that it can adapt to a wide range of olefin raw materials. No matter terminal olefins or internal olefins or branched olefins can be used as raw materials for the preparation of alcohols. The main disadvantage is that the linearity of the product is relatively low. Low, affecting the application range of product alcohol. Because, unless there is a special purpose, people generally expect to get normal alcohols. Moreover, using this type of catalyst, the product of the first step is aldehyde, and the second step is required to hydrogenate the aldehyde into alcohol, and the catalyst must also be destructively recovered.

Later, it was found that the use of organophosphine-modified cobalt carbonyl complex catalysts not only reduced the reaction pressure to 5.0-8.0 MPa, but also produced alcohols from olefins in one step, which greatly reduced the burden of post-hydrogenation and made post-hydrogenation The process is reduced from the main process to the secondary auxiliary process. At the same time, the proportion of normal alcohol in the product alcohol of this process is also significantly increased. Generally, the content of normal alcohol in the product alcohol is not less than 80%. BP1191015 and US3420898 are one of the representatives of this type of process. This type of process does not need to destructively recover the cobalt complex catalyst, but the mother liquor is directly recycled after the catalyst is separated from the reaction stream under suitable conditions. This improvement not only saves a lot of metal cobalt or salt recovery equipment, but also reduces the consumption of catalyst in the reaction-separation cycle.

Obviously, it is very important to ensure that cobalt salts and ligands are not decomposed during repeated recycling in the process of using organophosphine complex transition metal catalysts, and how to reduce their losses to as low as possible, which can effectively reduce the cost of alcohol production.

In the above process, both the catalyst and the reaction product exist in the same reaction liquid during the homogeneous catalytic reaction, and it is necessary to separate the product or part of the product from the reaction liquid, and recycle the catalyst or catalyst mother liquid together with the solvent to the reaction system . There are many methods used to complete this separation process, such as: simple distillation, vacuum distillation, flash distillation, and pressure distillation under the protection of syngas. The main problem in the above-mentioned methods is that metal cobalt and its salts and organic phosphine ligands are lost during the separation process, especially when preparing high-carbon alcohols, the catalyst loss is more serious.

In order to solve the above problems, US4060557 proposes to use molecular distillation equipment for the separation of high-carbon alcohol products from olefins and catalysts.

The principles and techniques of molecular distillation have been included in many textbooks as well-known techniques. The separation of mixtures by molecular distillation equipment has the advantages of low separation temperature, short material residence time and high efficiency. It has more obvious effects on the separation of heat-sensitive compounds, such as transition metal carbonyl complex catalysts. The reason is that this type of molecular distillation equipment operates under a relatively high vacuum to reduce the separation temperature as much as possible. However, when the mixed liquid to be separated has a wide range of components and a large boiling point range, especially when it contains both high-boiling point compounds and non-condensable components (such as: the reaction liquid contains carbon monoxide and hydrogen), it is required to first remove the non-condensable The components are separated, and then the molecular distillation separation is carried out, otherwise the distillation efficiency per unit area of the molecular distillation equipment will be greatly reduced, or the distillation temperature will be greatly increased, causing a large amount of decomposition of the heat-sensitive compound-homogeneous catalyst, and the use of molecules will be lost. Significance of distillation equipment. Under negative pressure, most of the non-condensables such as carbon monoxide and hydrogen dissolved in the reaction liquid escape from the liquid phase, and the carbonyl complex cobalt transition metal catalyst also removes carbonyl and transforms into salts. It is easy to decompose into metal cobalt at a temperature of 100,000, resulting in permanent deactivation of the catalyst. This salt is also easy to form relatively stable complexes with compounds with coordination ability such as alkenes, alkynes, nitriles, and amines. Even in the presence of carbon monoxide and hydrogen, this complex is not easily transformed into a cobalt carbonyl complex catalyst required for the hydroformylation reaction of olefins, which reduces the utilization rate of the catalyst.

The present invention seeks an improved olefin oxo-synthesis alcohol production process from C9 to C15 olefins to C10 to C16 alcohols. This process enables the catalyst mother liquor separated by negative pressure to be reconverted into olefins in the shortest possible time. The carbonyl complex of the oxo catalyst avoids the contact of olefins with coordination ability with the separated catalyst mother liquor, so as to ensure the full utilization of the organic phosphine ligand and cobalt carbonyl as the catalyst. The present invention further seeks to reduce the separation operation temperature and improve the separation efficiency per unit area of the separator in the separation process of the catalyst mother liquor and the product alcohol, so as to reduce the loss of organic phosphine coordination and cobalt atoms, and adapt to the content of mixed olefins or olefins below 80% of the hydrocarbon mixture is used as raw material for alcohol production.

Compared with pure olefins, the use of hydrocarbon mixtures with an olefin content of less than 80% as raw materials for alcohol production has the advantages of low price and wide source of raw materials. Separation system causes large pressure. For example, the olefins obtained by cracking paraffin with an oil content of 8% (weight) generally have an olefin content of about 80% (weight). Since there are still 20% (weight) of inert substances in the olefin raw materials, it is difficult for the refining and post-processing of the product. Processing adds to the burden. Another object of the present invention is to improve the separation process and process in the prior art to reduce the burden of product post-treatment when using olefins with an olefin content of less than 80% as raw materials for alcohol production.

The purpose of the present invention can be achieved through the following measures:

According to the present invention, there can be provided a method of hydroformylation of olefins with 9 to 15 carbon atoms or their mixtures, or mixtures of the above olefins and other hydrocarbons (alkanes, cycloalkanes, etc.), to produce 10 to 16 A continuous process for alcohols containing 1,000 carbon atoms, this process includes:

An olefin hydroformylation reaction section, a product separation section and a recycling catalyst regeneration section are provided. The olefin hydroformylation reaction section consists of several cascade gas-liquid parallel-flow bubble columns:

The fluid supplied to the above-mentioned olefin hydroformylation reaction section is actually a predetermined volume of liquid olefin hydroformylation medium containing uniformly distributed; A complex olefin hydroformylation catalyst; (b) free ligand; (c) free carboxylate and basic cocatalyst;

Continuously supply synthesis gas to the above-mentioned olefin hydroformylation reaction section, _H2 /CO=2～2.3:1 (molar ratio);

Continuously provide the above-mentioned arbitrary substituted olefins or mixed olefins to the above-mentioned olefin hydroformylation reaction section;

Operating the above-mentioned olefin hydroformylation reaction section under olefin hydroformylation conditions;

The product separation section is composed of a low-level gas-liquid separator, an externally cooled thin film evaporator and an internally cooled thin film evaporator;

Pass into the olefin hydroformylation reaction stream to the above-mentioned product separation section;

Separation and recovery of gas phase carbon monoxide and hydrogen in the low-pressure gas-liquid separator of the above-mentioned separation section;

Separate and recover the carbon monoxide and hydrogen dissolved in the reaction liquid and most of the by-product alkanes, unreacted olefins and other inert substances in the external cooling thin film evaporator of the above separation section;

In the internal cooling type thin film evaporator of above-mentioned separation section, product alcohol is separated with a certain ratio, and comprises whole catalyst-cobalt and its salts and ligands in the residue;

In the above-mentioned separation section, operate the above-mentioned separation section according to the evaporation conditions of different isolates,

Continuous circulation of the above-mentioned gas-liquid flow to the above-mentioned olefin hydroformylation reaction section;

The catalyst regeneration section consists of a catalyst circulation tank and a packed bubble column regenerator with a steam jacket;

Filling the above-mentioned catalyst circulation tank with actually a predetermined amount of synthesis gas;

Inject a predetermined flow rate of circulating catalyst solution and synthesis gas from the catalyst circulation tank to the above-mentioned catalyst packed bubble column, and replenish a predetermined amount of new catalyst at the same time;

The regeneration section described above is operated under regenerative conditions.

The olefin hydroformylation reactor composed of several series-connected tube-type gas-liquid parallel-flow bubble columns can be equipped with only one reactor, or two or more. The catalyst solution, syngas and reaction raw material olefins flowing out from the top of the regenerator all enter the reactor from the bottom of the reactor, and the reaction mixture passes through each reactor in a gas-liquid co-current manner, and the reaction stream flowing out from the last reactor includes: The product alcohol, by-product alkanes and a small amount of dimers, catalysts, unreacted olefins, inert substances contained in raw material olefins and the remaining synthesis gas, etc., the above gas-liquid mixtures are all injected into the separation section.

The gas-liquid separator in the separation section is a gas decompression discharge device with a predetermined volume, and the gas phase flow in the reaction liquid is discharged out of the container at a certain pressure. Then the liquid phase flow of the reaction flow enters the external cooling thin film evaporator. In this equipment, not only the dissolved carbon monoxide and hydrogen in the reaction liquid are removed, but also most of the by-product alkanes, unreacted olefins and raw materials are removed. Low-boiling inert substances, the liquid flowing out from the bottom of the evaporator is mainly product alcohol and heavy component substances, as well as catalysts. These mixtures continue to enter the inner-cooled thin film evaporator, in which the product alcohol is steamed out in a certain proportion, and the residue contains all catalysts-cobalt and its salts and ligands.

The catalyst obtained from the inner-cooled thin-film evaporator flows into the catalyst circulation tank. There are two circulation tanks arranged side by side, and one of the two circulation tanks is always collecting catalyst. The other one conveys the working status of the catalyst, and the two are switched at regular intervals. After one unit is full, fill it with synthesis gas, and use a pump or air pressure to send the catalyst into the regenerator. The regenerator is composed of a packed bubble column with a steam jacket, and its volume is equivalent to one-tenth of the volume of the reactor. To one-eighth, a predetermined flow rate of circulating catalyst solution and syngas is injected from the bottom, and a small amount of new catalyst solution is injected at the same time, and the gas and liquid phases flow from the top of the regenerator to the reaction section at the same time.

Readers in the technical field will recognize that the present invention does not belong to the invention category of any new olefin hydroformylation synthesis reaction or new chemical principle alcohol production system, and the present invention is only an improvement of the prior art process. That is: the prior art (US3, 448, 157, The two-stage process of US3,369,050) is improved to a three-stage process. The present invention fully proves the necessity of adding a regeneration section before the reaction section through the characterization of the in-situ spectrum and the comparison of examples. In addition, in order to meet the needs of the mixed fraction with an olefin content of less than 80% as a raw material for alcohol production, an externally cooled vacuum thin film evaporator is used to replace the vacuum degasser of the prior art (US4,060,557), and the separation from The circulation equipment and process of the catalyst solution from the section to the regenerator, the above-mentioned improvement of the present invention not only minimizes the decomposition of the cobalt carbonyl complex catalyst in the separation section, but also makes the most catalytically active catalyst active species: phosphine coordination The hydrogenated cobalt carbonyl component is fully contacted with olefins, which not only improves the efficiency of the catalyst and the reaction device, but also reduces the decomposition of the catalyst in the reaction section to a satisfactory degree, and at the same time alleviates the problem caused by the use of low olefin concentration fractions. Alcohol raw materials increase the burden on product post-processing (alkali washing, water washing, distillation, etc.).

Originally, the partial decomposition of the cobalt-phosphine carbonyl complex catalyst is unavoidable when it is recycled in the reaction and separation sections. The reason for its decomposition: on the one hand, the oxygen and sulfur brought in by the raw materials destroy the valence state of the phosphorus atom, making it change from trivalent to pentavalent, and lose its coordination ability; The coordination carbonyl groups in the catalyst active substances in the solution and in equilibrium with these catalyst active substances, or as the precursor of the catalyst active substances, all escape, and the cobalt atom loses its stable penta-ligand structure, and it is easy to form Cobalt metal deposits on the container walls. Adopt in-situ infrared technology to test the in-situ infrared spectrum of the reaction solution in the reaction section, the spectrogram is shown in Figure 2, and the attribution of each absorption peak is as follows:

A: 2045cm ^-1 and 1970cm ^-1 belong to HCo(CO) ₃ L

B: 2010cm ^-1 and 1998cm ^-1 belong to Co ₂ (CO) ₇ L

C: 1950cm ^-1 attributed to Co ₂ (CO) ₆ L ₂

D: 1923 cm ^-1 attributed to HCo(CO) ₂ L ₂

E: 1910cm ^-1 attributed to [Co(CO) ₄ ] ^-

F: 1880cm ^-1 and 1620cm ^-1 belong to RCH＝CH ₂

G: 1740cm ^-1 belongs to RCHO

H: 1710cm ^-1 attributed to RCOOH

Among them: the interval from 2045 to 1910 ^-1 is the absorption band of cobalt phosphine carbonyl complex. In the vacuum state of the separation section, the in-situ infrared spectrum bands in the range of 2045-1910 cm ^-1 all disappeared (see Figure 3), indicating that the cobalt phosphine carbonyl complex does not exist in the separation residual liquid or distilled liquid, and the cobalt atoms may be related to the free The organophosphine and naphthenate radicals generate an organophosphine-coordinated naphthenate cobalt salt. The properties of such salts have been discussed in detail. If this cobalt salt is in contact with olefins, it will generate unstable new complexes, and metal cobalt can be decomposed at a mild temperature higher than room temperature, causing permanent deactivation. If it is in contact with synthesis gas before contacting with olefins, At about 120°C, carbonyl complexes such as A, B, C, D, and E are formed. Figure 4 clearly shows this change. Some of these complexes are catalytically active and react with other complexes in hydroformylation condition to reach a balance. Owing to the presence of these catalytically active substances, olefins can be converted into alcohols. Obviously, since the present invention has improved the process in which the circulating catalyst directly enters the reaction section from the separation section in the prior art, a regeneration section with a small volume and a simple structure is added in front of the reaction section, which can fully reduce the decomposition of the catalyst in the reaction section and make the olefins Direct contact with the most catalytically active catalyst active species, monophosphine-coordinated hydrocobalt carbonyl, etc., instead of directly contacting the catalyst recovered from the separation section, is undoubtedly beneficial to improving the reaction efficiency and reducing the loss of the catalyst. In the prior art process, the first reactor, especially the lower part of the reactor, is actually a catalyst regenerator. It should be noted that when the catalyst recovered from the separation section, together with carbon monoxide and hydrogen and olefin feedstock After entering the first reactor, the recovered catalyst must first be contacted with syngas to be converted into catalytically active species in order to catalyze the hydroformylation reaction of olefins. However, when the catalyst is in contact with syngas, it is inevitably The olefins entering the reactor are also exposed, and the hazards of this exposure have been described clearly. The addition of the regeneration section in the process of the present invention avoids contact between the catalyst and olefins before generating active species, not only effectively improves the utilization rate of the lower part of the first reactor, but more importantly reduces the consumption of the catalyst. Through the above improvements, we have achieved one of the objectives of the present invention.

的内烯基。有代表性的烯烃包括，1-壬烯、2-壬烯、3-壬烯、1-癸烯、2-癸烯、3-癸烯、1-十一烯、3-十一烯、1-十二烯、4-十二烯、1-十三烯、3-十三烯、4-十三烯、1-十四烯、1-十五烯、3-十五烯等等。本发明的原料烯烃也可选自含其他烃类的馏分，这类烯烃通常来自石蜡裂解、重油热裂解及叠合汽油等。当本发明使用上述烯烃含量低于80%的原料时，其典型的组份大约为：C9～C14正构烯烃76%（重量），C9～C14烷烃15%，C9～C14异构烯烃3%，C9～C14双烯烃或炔烃3%，C9～C14芳烃3%，未知组份1%。 当然我们期望原料中有较高含量的正构烯烃。This process can be adapted to olefins with 9 to 15 carbon atoms. Such olefins can be not only terminal olefins or internal olefins, but also mixed olefins, especially for mixed hydrocarbons with an olefin content of less than 80%. That is, the chemical formula -CH=CH ₂ or C=CH ₂ α-alkenyl or

the inner alkenyl. Representative alkenes include, 1-nonene, 2-nonene, 3-nonene, 1-decene, 2-decene, 3-decene, 1-undecene, 3-undecene, 1 -dodecene, 4-dodecene, 1-tridecene, 3-tridecene, 4-tridecene, 1-tetradecene, 1-pentadecene, 3-pentadecene and the like. The raw material olefins of the present invention can also be selected from fractions containing other hydrocarbons, such olefins usually come from paraffin cracking, heavy oil thermal cracking and composite gasoline, etc. When the present invention uses the raw material with the above-mentioned olefin content lower than 80%, its typical composition is about: C9～C14 normal olefin 76% (weight), C9～C14 alkane 15%, C9～C14 isomeric olefin 3% , C9 ~ C14 diolefins or alkynes 3%, C9 ~ C14 aromatics 3%, unknown components 1%. Of course we expect a higher content of normal olefins in the feedstock.

Obviously, when raw material olefins with different carbon numbers and structures are used, phosphine ligands with different structures and boiling points should be selected. Usually, the boiling point of the phosphine ligands should be higher than that of the product alcohol. The selected ligand of the present invention has:

Trialkyl tertiary phosphines: tri-n-butylphosphine, tri-n-octylphosphine, tri-n-hexadecylphosphine or diethylhexadecylphosphine, dibutylhexadecylphosphine.

Trialkylarylphosphines: diethylphenylphosphine, ethyldiphenylphosphine, dibutylphenylphosphine, butyldiphenylphosphine, diethylnaphthylphosphine or dibutylnaphthylphosphine.

Cyclic phosphines: 9-phosphine bicyclononane octadecyl phosphine, polycyclic monophosphine or polycyclic diphosphine, etc.

The reaction medium includes a cobalt phosphine carbonyl complex catalyst composed of carbon monoxide and phosphine ligands in a complex manner. This catalyst can be produced in situ in the reaction medium, or it can be prepared in advance, preferably in advance. When the process flow of the present invention is in operation, the catalyst is actually prepared in advance in the regenerator, and then introduced into the reaction medium of. Methods of preparing active catalysts are, of course, well known in the art.

The content of cobalt in the reaction medium is 0.2-0.6% (by weight) or greater than 0.6% as calculated by metal cobalt, but it is better to be in the range of 0.40-0.45% from an economic point of view. The source of cobalt can be cobalt naphthenate, cobalt carboxylate, dicobalt octacarbonyl, diphosphine hexacarbonyl dicobalt and cobalt carbonate.

In the reaction medium, the ligand is usually in excess: P: Co (atom) = 4: 1 to 3: 1, the preferred ratio is P: Co = 2: 1. The usual scale is that there are at least 1.5 moles of free ligands per mole of cobalt catalyst.

To produce alcohol by operating the above-mentioned process under the condition of olefin hydroformylation, the conditions of reaction section, separation section and regeneration section can be selected according to raw material olefin, ligand, cobalt concentration and other efficiency factors. The same or similar temperature, pressure and other conditions are selected for the regeneration section and the reaction section. The reaction section usually adopts the conditions of 170~190°C, 5.0~8.0MPa and H ₂ /CO=2~2.3 (mole), and reacts for 6~12 hours. The better reaction conditions are 175~185°C, 5.0~ Operate at 6.0MPa for 7-9 hours. The regeneration section usually adopts the conditions of 165-175°C, 5.0-7.0MPa, H ₂ /CO=2-2.3, and regeneration time of 30-60 minutes. The two series-connected thin-film evaporators in the separation section also use the same or similar operating pressure, usually 0.1-50mmHg, the second thin-film evaporator operates at a higher vacuum than the first, and the separation temperature varies according to the separated objects The operating temperature of the first thin-film evaporator is usually 20-30°C lower than that of the second one, and the maximum temperature of the second one should not exceed 120°C, otherwise it will cause a large amount of decomposition of the catalyst. Relatively low operating pressures and temperatures are desirable for the present invention, if not otherwise detrimental.

The process operates differently when different feedstock olefins and catalysts are used. If a raw material with an olefin content of about 80% is used, the reaction stream flowing out from the reaction section is relatively complex, including product alcohol, by-product alkanes, unreacted olefins, free ligands, catalysts, a small amount of heavy components, and Inert substances and synthesis gas dissolved in the above liquid, and, unlike the use of higher purity olefins as raw materials, the concentration of alcohol in the reaction stream is only 60-65% instead of 85-90%. According to the prior art, a degassing tower is used to remove the synthesis gas dissolved in the reaction solution, and then the reaction solution enters the thin-film evaporator to separate the product alcohol and the catalyst. Because the boiling points of hydrocarbons and alcohols with the same carbon number differ by 80 ~100°C, in the thin film evaporator, part of the heating surface must be used for the evaporation of low-boiling hydrocarbons, which reduces the evaporation area for evaporating product alcohol, and with the increase of hydrocarbon content, the reduction is even greater. In order to ensure the stability of the catalyst and the yield of alcohol, the method is to increase the evaporation area, prolong the residence time of the catalyst under the distilled product alcohol, or increase the evaporation temperature. Obviously, the above measures are unfavorable factors for the stability of the thermosensitive catalyst and its precursor. The present invention adopts an externally cooled thin-film evaporator to replace the high-efficiency degassing tower of the prior art. Separation, depending on the number of carbon atoms of the hydrocarbons and alcohols in the reaction liquid, select an appropriate operating temperature. This shortens the residence time of the catalyst under vacuum and higher temperature, reduces the decomposition of the catalyst, reduces the deposition of cobalt on the wall of the thin-film evaporator, prolongs the cleaning cycle of the evaporator, and also reduces the post-treatment of the crude alcohol product burden.

The above-mentioned improvement of the present invention is preferably suitable for raw materials with low olefin content or complex composition, and the boiling point of each main component of the reaction solution listed in the table below is just a reflection of using this type of crude raw material:

Carbon boiling point (°C) 0.1mmHg boiling point (°C)

Alkanes Alkenes-n Alcohols-n Alkanes-n Alcohols-n

C5 36.1 30 137.3 ⁷⁴⁸ , 50 ¹³ / / /

C6 68.7 63.3 158 / / / /

C7 98.4 93.6 176.3, 78-9 ¹⁵ // ~0

C8 125.6 121.3 194-195 / / / ~17

C9 150.7 149.9 215 / / / ~30

C10 174 172 232.9 / / / ~43

C11 195.6 192-195 243 ～17 ～15～17 ～50

C12 213 213 259 ～32 ～32 ～60

C13 235.4 232.8 274 ～45 ～43 ～70

C14 253.7 246 170-3 ²⁰ ～55 ～51 ～81～85

C15 270.5 268.2 299 ～65 ～62 ～85

C16 287 284.5 190 ¹⁵ ～76 ～75 ～106

If the raw material olefin with higher purity is used, the components of the reaction solution are much simpler. At this time, of course, only one thin film evaporator can be considered.

For a better understanding of the present invention, we propose the following examples.

example 1:

This example is a comparative example with or without a regenerator.

In the technical process and device of Fig. 1, 2-ethylhexanol is used as solvent, cobalt naphthenate and octadecyl bicyclononylphosphine are raw materials for making catalyst, and the cobalt content prepared in situ is 0.4% (weight). The cobalt phosphine carbonyl complex catalyst, its reaction result is:

With regenerator Without regenerator

Cobalt metal content (weight%) 0.4 0.4

P/Co (mol) 2 2

H ₂ /CO (mol) 2 2

Regenerator temperature (°C) 107±5 /

Regenerator pressure (MPa) 5.0 /

Reactor temperature (°C) 180±5 180±5

Reactor pressure (MPa) 5.0 5.0

Olefin content 76% 76%

(C9～C14)

Continuous running time (hours) 400 400

Olefin conversion rate 94% 90%

Primary alcohol yield (weight) 103 98

Alkanes yield (weight) 8.01 8.1

Organic phosphine consumption 1.98 2.56

(kg/ton alcohol)

Example 2

In the autoclave, sequentially add 4.5 parts of cobalt naphthenate, 4.5 parts of tributylphosphine, 1 part of cocatalyst KOH and 90 parts of solvent 2-ethylhexanol, stir and raise the temperature, and fill the synthesis gas under the conditions of 170 ° C and 4.0 MPa After 4 hours, it was qualified by in-situ infrared monitoring, that is, the absorption at 1970 and 2045 cm ^-1 reached saturation. The prepared catalyst solution is mixed with the circulating catalyst via the line 18 and the pump 34, and the catalyst is added to regenerate a reaction circulation system.

The raw material olefin (line 2) is boosted by the high-pressure metering pump 33 and passes through the preheater 36, then merges with the purified synthesis gas (line 1, H ₂ CO is 2-2.1) and then enters the reactor 22, and the top of the regenerator 21 The outflowing catalyst and synthesis gas are sprayed into the reactor 22 from the bottom through the sinking tube 65 and distributor 62, and react under the conditions of 170-180°C and 5.0-7.0 MPa. The reaction liquid flowing out of the reactor 22 flows into the reactor 23 through the bottom pipe 66 and the gas-liquid distributor 63 , and the reaction liquid flowing out of the reactor 23 enters the reactor 24 through the bottom pipe 67 and the distributor 64 . The heat of reaction is removed by the jacket of each reactor and the tempering water in the inner cooling tube. The warming water (line 68) flows into the steam drum 32 after decompression, and the low-pressure steam (line 19) is separated, and the corresponding cold water (line 20) is supplemented, and the pressure is increased by the pump 35 and adjusted by the heat exchangers 40 and 41 to become temperature-adjusted water. The gas-liquid mixture flowing out of the last reactor 24 enters the gas-liquid separator 25, and the unreacted synthesis gas (line 5) is decompressed and discharged into the fuel gas main pipe. The reaction liquid enters the external cooling thin-film evaporator 26 after being adjusted by the cooler 37. The evaporation temperature is controlled at 60-70°C and the pressure is 15mmHg (absolute pressure). The alcohol and the catalyst are separated, and the evaporated alkanes and olefins are received after being cooled by the cooler 38. A small amount of alkanes, olefins, alcohols and catalysts that have not evaporated flow into the internal cooling thin film evaporator 27, and are separated into two streams of crude alcohol and catalyst under the conditions of evaporation temperature of 90-95°C and pressure of 0.1-0.5mmHg (absolute pressure). materials. The crude alcohol is mixed with the alkanes and hydrocarbons evaporated by the evaporator 26, and sent to the subsequent working section for refining treatment. The catalyst cooled by the cooler 39 is received by the receiving tanks 28 and 29, and matched with the catalyst circulation tanks 30 and 31 to realize the continuous circulation of the catalyst, and regularly and quantitatively discharge part of the spent catalyst (line 15). The circulation tanks 30 and 31 are filled with 0.2-0.4 MPa synthetic gas for protection. Intermittently replenished fresh catalyst (line 18) is mixed with the circulating catalyst through metering pump 34, and then mixed with a small amount of synthesis gas and injected into the regenerator to maintain the regeneration conditions of 160-170°C and 5.0-7.0 MPa, and the liquid stays for 0.5-1 Hours later, the gas-liquid mixture is injected into the reactor from the top of the regenerator through the distributor 62 at the bottom of the reactor.

The C9-C11 mixed olefin fraction with an olefin content of 79% (weight) and an alkane content of 15% (weight) is used as a raw material, the cobalt concentration of the catalyst is 0.4% (weight), and the phosphine-cobalt ratio is 2:1 (mol), the ratio of synthesis gas to olefin is 4-5:1 (mol), the ratio of circulating catalyst/olefin is 0.67-2.5:1 (volume ratio, generally 1.6:1), and the total liquid reaction residence time is 7.7-12 Hours (generally 9 hours), in the above device, continuous operation for 1000 hours, the average weight yield of C10～C12 alcohol is 90%.

Example 3

The phosphine ligand is a mixture of sixteen to twenty mixed alkyl-9-phosphine bicyclononanes with an α-olefin content of 76% by weight. C8-C16 mixed olefins composed of 10-15% alkanes, 10-14% isoparaffins, olefins and unknowns are used as raw materials, of which C11-C14 olefins account for 85%. Using the same method and device described in Example 2, the total residence time of the liquid is 6.72 to 10.22 hours (preferably 9 to 10 hours), the circulation catalyst and the olefin volume ratio are 0.54 to 2: 1 (preferably 0.54 to 0.67: 1) Under the conditions of 4.69-8.63:1 (mol) synthesis gas/olefin (preferably 4.5-5.0:1), the average yield of C9-C17 alcohols is 99.54% (by weight) after continuous operation for 1000 hours. Under optimal reaction conditions, the weight yield of higher alcohols can reach 100-105%. In this operation, the evaporation conditions of the external cooling thin film evaporator are temperature 70-80°C and pressure 10mmHg (absolute pressure) and the operating conditions of internal cooling thin film evaporator are temperature 95-105°C and pressure 0.2mmHg (absolute pressure). pressure).

Claims (9)

1. A continuous process for producing alcohols with 10 to 16 carbon numbers by subjecting randomly substituted olefins with 9 to 15 carbon numbers to olefin hydroformylation, including: Provide an olefin hydroformylation reaction section and a product separation section; The olefin hydroformylation reaction section is composed of several series-connected gas-liquid parallel-flow bubble columns; The fluid provided to the above-mentioned olefin hydroformylation reaction section is actually a predetermined volume of olefin hydroformylation catalyst liquid, which contains uniformly distributed: (1) containing carbon monoxide and organic phosphine ligands combined in a coordinated manner Cobalt complex olefin hydroformylation catalyst; (2) free ligand; (3) free carboxylate and basic promoter; Continuously supply carbon monoxide and hydrogen to the above-mentioned olefin hydroformation section; Continuous supply of the above-mentioned optionally substituted olefins to the above-mentioned olefin hydroformylation section; Operating the above-mentioned olefin hydroformylation reaction section under olefin hydroformylation conditions; The separation section consists of a series of low-pressure gas-liquid separators and thin-film evaporators; Pass into the olefin hydroformylation reaction stream to the above-mentioned product separation section; operating said separation section under separation conditions; Continuously recycle the above-mentioned gas-liquid stream to the above-mentioned olefin hydroformylation reaction; It is characterized by: providing a catalyst regeneration section and means for recycling liquid between the separation section and the regeneration section; The catalyst regeneration section is composed of a catalyst circulation tank filled with 0.2-0.4MPa synthesis gas and a packed bubble column regenerator with a steam jacket. The volume of the bubble column is 1/10-1/8 of the total volume of the reactor ; Provide a film evaporator consisting of an external cooling thin film evaporator and an internal cooling thin film evaporator in series. The external cooling is 20-30°C lower than the internal cooling thin film evaporator, and the internal cooling thin film evaporator does not Operate under conditions greater than 120°C; Inject a predetermined amount of circulating catalyst solution and synthesis gas from the catalyst circulation tank to the catalyst regenerator, and replenish a predetermined amount of new catalyst at the same time; The catalyst regeneration condition is 185-175° C. and 5.0-7.0 MPa, and the operation is 0.5-1.0 hour. 2. A process according to claim 1, characterized in that the optionally substituted olefin has 9 to 15 carbon atoms. 3. The process according to claim 1 or 2, characterized in that the randomly substituted olefins are selected from the group consisting of paraffin cracked olefins, heavy oil pyrolysis olefins, composite gasoline olefins and other hydrocarbons with an oil content of not more than 8% (weight). Mixed olefins. 4. The process according to claim 1, characterized in that any substituted olefins are selected from paraffin cracking fractions, which are composed of: C ₉ ~ C ₁₀ normal olefins 78% (weight), C ₉ ~ C ₁₀ alkanes 15%, C ₉ -C ₁₀ isomeric olefins 3%, C ₉ -C ₁₀ diolefins or alkynes 3%, other fractions 4%, and the ligand is a trialkyl tertiary phosphine. 5. The process according to claim 1, characterized in that any substituted olefins are selected from paraffin cracking fractions, which are composed of: 78% (weight) of C ₁₁ ~C ₁₄ normal olefins, 15% of C ₁₁ ~C ₁₄ alkanes, C ₁₁ -C ₁₄ isomeric olefins 3%, C ₁₁ -C ₁₄ diolefins or alkynes 3%, C ₁₁ -C ₁₄ aromatics 3%, other components 1%, and the ligand is a bicyclic phosphine heterocycloalkane base tertiary phosphine. 6. A process according to claim 1 wherein the olefin hydroformylation medium contains, calculated as cobalt metal, about 0.2 to 0.6 cobalt and at least 1.5 to 2 moles of free ligand per mole of cobalt catalyst. 7. A process according to claim 8, characterized in that the cobalt concentration in the olefin hydroformylation mesoformylation medium ranges from 0.4 to 0.45% by weight. 8. The process according to claim 1, characterized in that the olefin hydroformylation conditions are: operating at a temperature of 175-185°C and a pressure of 5.0-8.0 MPa for 6-12 hours. 9. The process according to claim 7, characterized in that the hydroformylation condition is: operating at a temperature of 175-185°C and a pressure of 5.0-6,0 MPa for 7-9 hours.

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