A continuous phase separation reactor and a method for preparing vitamin E acetate

Abstract

The present invention provides a continuous phase-separation reactor for preparing vitamin E acetate and a liquid-phase catalyst for the synthesis of vitamin E acetate. The reactor includes a reaction liquid collection area, a honeycomb-like channel separation area, a phase separation area, a reaction area, a catalyst separation area, a catalyst collection area, a stirring area, and necessary auxiliary structures from top to bottom. This reactor is suitable for a liquid-liquid two-phase reaction system, and can separate the reaction liquid and the catalyst after the reaction, thereby improving the efficiency and life of the catalyst in the system. The liquid-phase catalyst used for the synthesis of vitamin E acetate in combination with this system can meet the purity requirements after light and heavy removal of the vitamin E acetate obtained after the reaction. This reaction system is intended to improve the synthesis efficiency of vitamin E acetate, inhibit side reactions, improve the conversion rate and selectivity of the reaction, and avoid the complex separation process and catalyst application process of the subsequent reaction liquid.

Description

Technical Field

[0001] The invention relates to a continuous phase-separation reactor and a method for preparing vitamin E acetate by using the reactor, belonging to the technical field of vitamin E acetate production and the field of reactors. Background Art

[0002] Vitamin E acetate is a kind of vitamin E derivative. Its hydrolysis product, vitamin E, is a fat-soluble vitamin, also known as tocopherol, a kind of antioxidant. Vitamin E can improve the fertility of animals, for example, it can increase the number and activity of male sperm, promote the production of female estrogen, and improve fertility. Vitamin E can also be used for beauty, treatment of frostbite, burns, etc. At present, more than 80% of the vitamin E on the market is artificially synthesized. As people pay more attention to health, vitamin E will have a broader application market and commercial value.

[0003] German patent DE2000111402 discloses a method for using aqueous protonic acid and zinc halide (Lewis acid) as catalysts to carry out a reaction of synthesizing vitamin E acetate from isophytol and 2,3,5-trimethylhydroquinone diester in a mixture of polar solvent and water. The catalyst uses relatively cheap aqueous protonic acid and zinc halide, and can be used for large-scale industrial production, but it will produce a large amount of waste catalyst and wastewater. The aqueous protonic acid will cause relatively serious corrosion to the equipment, and subsequent treatment is difficult; and the reaction generates vitamin E acetate and vitamin E mixture. Vitamin E is unstable and is easily oxidized and deteriorated to lose its activity. Subsequently, acetic anhydride needs to be added to carry out an esterification reaction to convert vitamin E into vitamin E acetate for subsequent processing.

[0004] Chinese patent CN 111646968 A discloses a solid catalyst synthesized from a metal oxide-supported heteropolyacid and triphenylphosphine. The solid catalyst is used for the reaction to realize catalyst recycling, inhibit the generation of side reactions, and avoid subsequent esterification reactions. However, the subsequent system has solid and liquid separation, solid transportation, and a large amount of catalyst is used, which also causes the complexity of the process.

[0005] European patent EP01104141.5 uses biological esterase as a catalyst, trimethylhydroquinone diethyl ester is first converted into trimethylhydroquinone-4-acetate, and finally vitamin E acetate is obtained by condensation. If biological enzymes are used as catalysts, high production costs will be generated, which is not conducive to large-scale production. In addition, the activity of biological enzymes is significantly affected by temperature, and harsh reaction conditions cannot be selected.

[0006] The reactors used for the synthesis of vitamin E acetate are mostly intermittent reactors, which have the advantages of strong adaptability, simple and reliable structure. However, after the reaction, the subsequent catalyst and reaction liquid need to be separated. Since the catalyst is mostly Lewis ionic liquid catalyst, it is often accompanied by chemical processes such as filtration, extraction, and distillation, which increases the complexity of subsequent separation and is not conducive to capacity improvement.

[0007] Therefore, finding an efficient and continuous vitamin E acetate synthesis reactor, combined with a cheap and highly active catalyst, is of great significance for improving the reaction efficiency, inhibiting the occurrence of side reactions, and simplifying the subsequent separation process. Summary of the invention

[0008] In view of the above-mentioned problems existing in the prior art, the present invention provides a continuous phase-separation reactor, which has a honeycomb channel separation zone, a phase separation zone, a reaction zone, a catalyst separation zone and other structures, and is applied to a liquid-liquid two-phase reaction system; the reactor can achieve complete separation of liquid catalyst and reaction liquid, and the collected reaction liquid can obtain a product with high purity through simple refining; the concentration distribution of the catalyst phase in the reaction zone can increase the reaction rate and avoid the tailing phenomenon of the reaction.

[0009] The present invention also provides a high-efficiency catalyst for synthesizing vitamin E acetate, which can inhibit the generation of side reactions, improve the reaction conversion rate and yield, and the catalyst can be separated from the reaction liquid in the reactor, which is convenient for the reuse of the catalyst.

[0010] To achieve the above object, the present invention is implemented through the following technical solutions:

[0011] A continuous phase-separation reactor comprises a reaction liquid collection zone, a honeycomb-like channel separation zone, a phase-separation zone, a plurality of reaction zones, a reaction zone partition, a catalyst separation zone, and a catalyst collection zone; the top of the reactor is the reaction liquid collection zone, a reaction liquid outlet is arranged outside the reaction liquid collection zone, the lower part of the reaction liquid collection zone is connected to the upper packing layer of the honeycomb-like channel separation zone, the inlet of the honeycomb-like channel is connected to the phase-separation zone, a plurality of reaction zones are located at the lower part of the phase-separation zone, the phase-separation zone and the reaction zone are separated by a partition, stirring is arranged in the reaction zone, a reaction raw material inlet and a catalyst inlet are arranged outside the reaction zone, preferably the catalyst inlet is located at the upper part of the reaction zone, the reaction raw material inlet is located at the lower part of the reaction zone, the reaction zones are separated by partitions, the bottom of the reaction zone is connected to the catalyst separation zone, the lower part of the catalyst separation zone is connected to the catalyst collection zone, and a catalyst outlet is arranged outside the catalyst collection zone.

[0012] In the reactor of the present invention, the honeycomb-like channel separation zone has a channel front end connected to the reaction zone and is composed of a honeycomb-like channel, and its channel structure is triangular, square, pentagonal, hexagonal or circular, preferably hexagonal, circular, and more preferably hexagonal.

[0013] In the reactor of the present invention, the channel surface comprises a plastic or resin with lipophilic and hydrophobic groups, wherein the lipophilic and hydrophobic groups are hydrocarbon groups containing C10 to C20, hydrocarbon groups containing polyoxypropylene groups, polysiloxane groups or long-chain perfluoro groups, hydrocarbon groups containing aromatic groups, amide groups, amine groups, ether bonds, ester groups and the like; hydrocarbon groups containing ester groups and ether bonds are preferred.

[0014] As a preferred solution, the area of ​​a single small channel of the hexagonal channel is 0.001 to 0.1 times, preferably 0.01 to 0.08 times, of the cross-sectional area of ​​the reaction zone, and the channel length is 0.5 to 2 times, preferably 0.8 to 1.2 times, of the cross-sectional diameter of the reaction zone;

[0015] The bottom of the hexagonal flow channel is connected to the packing layer, which is a composite of oleophilic and hydrophobic fibers or oleophilic and hydrophobic particles and activated carbon. The mass ratio of the oleophilic and hydrophobic fibers or oleophilic and hydrophobic particles to the activated carbon is 1:0.1-1, preferably 1:0.2-0.5, and the height of the packing layer is 0.001-0.2m, preferably 0.005-0.02m.

[0016] In the reactor of the present invention, the reaction zone is a plurality of reaction zones having circular hole-shaped channels separated by partitions, which may be 1 to 10 reaction zones, preferably 2 to 4 reaction zones;.

[0017] In the reactor of the present invention, the catalyst separation zone is connected to the bottom of the reaction zone, and the catalyst separation zone is composed of an inclined plate with a certain gap, the inclination angle of the inclined plate to the horizontal plane is 90-45°, preferably 80-60°, the inclined plate gap is 0.02-0.2 times the diameter of the reaction zone, preferably 0.05-0.1 times, and the height of the inclined plate zone is 0.2-2 times the diameter of the reaction zone, preferably 0.3-1.2 times;

[0018] The present invention also provides a method for preparing vitamin E acetate, wherein the catalyst enters from a catalyst inlet at the top of a reaction zone; the reaction raw materials, isophytol, 2,3,5-trimethylhydroquinone diester and a solvent, enter from a raw material feed port at the bottom of the reaction zone; after the reactants and the catalyst are fully reacted, the reaction products and the solvent are mainly non-polar lipophilic components, which are separated in a phase separation zone and a honeycomb-like channel at the top of the reactor and enter a reaction liquid collection zone; the catalyst is mainly hydrophilic polar components, which are separated in a bottom catalyst separation zone and enter a catalyst collection zone; an external pump circulation system can be provided, and the bottom catalyst is circulated to the catalyst feed port at the top of the reaction zone through a pump, and enters the reactor reaction zone again for reaction, thereby realizing catalyst reuse.

[0019] The molar ratio of 2,3,5-trimethylhydroquinone diester to isophytol is 1:0.8-2.0, preferably 1-1.3; and / or, the reaction temperature of the reaction is 30-100°C, preferably 40-80°C, and the reaction pressure of the reaction is 0-0.5MPaG, preferably 0-0.1MPaG. ;

[0020] The solvents used are C5-C18 straight-chain alkanes, chlorinated alkanes, branched-chain alkanes, and ethers; C6-C12 aromatic hydrocarbons; wherein the C5-C18 straight-chain alkanes, branched-chain alkanes, chlorinated alkanes, and ethers are preferably one or more of n-hexane, n-heptane, and petroleum ether; the C6-C9 aromatic hydrocarbons are preferably one or more of benzene, ethylbenzene, and toluene; the amount of the solvent used is 0.6-2 times the mass of 2,3,5-trimethylhydroquinone diester, preferably 0.8-1.2 times.

[0021] The catalyst is a liquid mixture containing metal halide, water, palladium ions, acetic acid, hydrochloric acid and a stabilizer, and is composed of: 20-65wt% metal halide, 32-41wt% water, 1-11wt% palladium ions, 0.6-21wt% acetic acid, 0.6-7wt% hydrochloric acid, and 0.6-7wt% stabilizer. The catalyst preparation comprises the following steps:

[0022] Step 1: Mix the metal halide with water and then add metal palladium, acetic acid and dilute hydrochloric acid;

[0023] Preferably, the mass ratio of metal halide to water is 1:0.5-2, and the mass ratio of metal halide to metal palladium, acetic acid, hydrochloric acid, and stabilizer is 1:0.02-0.5:0.01-1:0.01-0.3:0.01-0.1. Step 2: Raise the temperature to 50-90°C, reflux for 2-8 hours, and stop the reaction after the metal palladium is completely dissolved;

[0024] Preferably, the reaction temperature is 60-80°C and the reaction time is 3-5h;

[0025] Step 3: Add bis(triphenylphosphine)copper dichloride or bis(triphenylphosphine)ferric dichloride or bis(triphenylphosphine)zinc dichloride as a stabilizer and mix evenly. The added amount is 0.01-0.1 times of the metal halide.

[0026] Preferably, the stabilizer is bis(triphenylphosphine)zinc dichloride.

[0027] Preferably, the amount of the stabilizer added is 0.01-0.05 times that of the metal halide.

[0028] The metal halide is selected from one or more of cupric chloride, zinc chloride, ferric chloride, palladium chloride and ferrous iodide.

[0029] The mass of the catalyst used is 0.004-0.09 times, preferably 0.01-0.05 times, of the mass of 2,3,5-trimethylhydroquinone diester.

[0030] The positive effect of the present invention is that the present invention can realize the continuous production of vitamin E acetate by using a continuous phase separation reactor, and its honeycomb channel-like catalyst and reaction liquid separation structure can realize the separation of the catalyst phase and the reaction liquid, and realize the recycling of the catalyst. The method of the present invention can increase the reaction conversion rate to more than 99% and the selectivity to more than 98%. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 Schematic diagram of the continuous phase separation reactor structure of Example 1

[0032] Figure 2 A schematic top view of the structure of the honeycomb-like channel separation area of ​​Example 1

[0033] Figure 3 Schematic diagram of the three-dimensional structure of the honeycomb-like channel of Example 1

[0034] Figure 4 The schematic diagram of the structure of the inclined plate separator of Example 1 is DETAILED DESCRIPTION

[0035] The technical solution of the present invention is further described in detail below through examples and drawings, but the present invention is not limited thereto.

[0036] The main raw materials used in the examples of the present invention are from information sources, and other materials are common commercially available raw materials unless otherwise specified. The hydrochloric acid used in the present invention is a hydrochloric acid aqueous solution with a mass concentration of 37.5%.

[0037] The product selectivity and conversion rate involved in the embodiment were analyzed by gas chromatography. The gas chromatography conditions were as follows: the gas chromatograph was Agilent 7820A, the capillary column was (DB-5, 30m×0.25mm×0.25μm), the temperature was programmed in two stages, the initial temperature was 100°C, and the temperature was raised to 130°C at a rate of 5°C / min after being maintained for 2 minutes; then the temperature was raised to 280°C at a rate of 15°C / min and maintained for 22 minutes. The carrier gas was high-purity N2, with a split ratio of 20:1. The injection temperature was 290°C, the detector was FID, the detector temperature was 300°C, and the injection volume was 0.2μL.

[0038] Example 1

[0039] A continuous phase separation reactor, the structure of which is as follows Figure 1 to Figure 4 As shown, it includes a reaction liquid collecting zone 1, a honeycomb channel separation zone 2, a phase separation zone 3, a reaction zone 4, a reaction zone partition 5, a catalyst separation zone 6, a catalyst collecting zone 7, an agitator 8, a reaction liquid outlet 9, a catalyst inlet 10, a reaction raw material inlet 11, and a catalyst outlet 12; the top of the reactor is the reaction liquid collecting zone 1, the lower part of the reaction liquid collecting zone 1 is connected to the upper packing layer of the honeycomb channel separation zone 2, the inlet of the honeycomb channel is connected to the phase separation zone 3, the phase separation zone 3 and the reaction zone 4 are separated by a partition, a stirring device 8 is arranged in the reaction zone, the reaction zones are separated by a partition 5, the bottom of the reaction zone is connected to the catalyst separation zone 6, and the outlet of the catalyst separation zone 6 is connected to the catalyst collecting zone 7.

[0040] The diameter of the reaction zone is 0.3m, the height of a single reaction zone is 0.8m, the diameter of the reaction liquid collection zone is 0.5m, and the height is 1.1m;

[0041] The honeycomb-like channel selects a hexagonal channel, whose channel area is 0.08 times the cross-sectional area of ​​the reaction zone, the number of channels is 91, and the channel length is 0.24m. An oleophilic and hydrophobic plastic containing an ester group is selected as the channel surface coating, and the bottom filler selects a mixture of oleophilic and hydrophobic particles (from Yuanjiang Chemical Co., Ltd. or Zhongke Jingna New Materials Technology Co., Ltd.) and activated carbon, according to the mass ratio of oleophilic and hydrophobic particles to activated carbon of 1:0.5, and the height of the filler layer is 0.02m;

[0042] Select a partition with 6 circular hole channels to divide the reaction zone into 3 parts, and set a stirring paddle in each reaction zone;

[0043] The height of the inclined plate area is 0.8 times the diameter of the reaction zone, the inclination angle of the inclined plate is 80°, the interval between the inclined plates is 0.02 times the diameter of the reaction zone, and the height of the inclined plate is 0.09m;

[0044] An external circulation pump is used to circulate the catalyst. The bottom catalyst leaves the catalyst collection area from the catalyst outlet 12 and enters the reaction area from the catalyst inlet 10. The prepared reaction liquid enters from the reaction raw material inlet 11. After the reaction is completed, the reaction liquid leaves the reactor from the reaction liquid outlet 9.

[0045] Example 2

[0046] The continuous phase separation reactor of Example 1 was used, except that a triangular channel was used, the area of ​​a single small channel was 0.01 times the cross-sectional area of ​​the reaction zone, and the channel length was 1.2 times the cross-sectional diameter of the reaction zone (3.6 m). An oleophilic and hydrophobic plastic containing an ether bond was selected as the channel surface coating, and the mass ratio of oleophilic and hydrophobic particles to activated carbon was 1:1, and the height of the packing layer was 0.005 m.

[0047] Example 3

[0048] The continuous phase separation reactor of Example 1 was used, except that a square channel was used, a single channel was 0.01 times the cross-sectional area of ​​the reaction zone, and the channel length was 0.8 times the cross-sectional area of ​​the reaction zone (0.24 m). The bottom filler was a mixture of oleophilic and hydrophobic particles and activated carbon, according to the mass ratio of oleophilic and hydrophobic particles to activated carbon of 1:0.1, the height of the filler layer was 0.02 m, and two reaction zones were used.

[0049] Example 4

[0050] The continuous phase-separated reactor of Example 1 is used, except that four reaction zones are used, the height of the inclined plate zone is twice the diameter of the reaction zone, the inclination angle of the inclined plate is 60°, the interval between the inclined plates is 0.2 times the diameter of the reaction zone, and the height of the inclined plate is 0.36 m.

[0051] Example 5

[0052] Zinc chloride and water are mixed in a mass ratio of 1:0.8, and stirred at room temperature until the zinc chloride is completely dissolved, and metal palladium with a mass of 0.2 times the mass of zinc chloride, acetic acid with a mass of 0.4 times the mass of zinc chloride, and hydrochloric acid with a mass of 0.02 times the mass of zinc chloride are added to the mixture; the temperature is raised to 80° C., and reflux reaction is performed for 3 hours; a liquid mixture of 40.4wt% zinc chloride, 32.4wt% water, 8.1wt% palladium ions, 16.2wt% acetic acid, and 0.8wt% hydrochloric acid is obtained, and finally bis(triphenylphosphine)zinc dichloride with a mass of 0.05 times the mass of zinc chloride is added to obtain the catalyst CAT1 required for the reaction.

[0053] Example 6

[0054] Zinc chloride and water are mixed in a mass ratio of 1:1.2, and stirred at room temperature until the zinc chloride is completely dissolved, and metal palladium with a mass of 0.2 times the mass of zinc chloride, acetic acid with a mass of 0.5 times the mass of zinc chloride, and hydrochloric acid with a mass of 0.1 times the mass of zinc chloride are added to the mixture; the temperature is raised to 60°C, and refluxed for reaction for 5 hours; a liquid mixture of 33.1wt% zinc chloride, 39.7wt% water, 6.6wt% palladium ions, 16.6wt% acetic acid, and 3.3wt% hydrochloric acid is obtained, and finally 0.02 times the mass of zinc chloride is added to di(triphenylphosphine)ferric dichloride to obtain the catalyst CAT2 required for the reaction.

[0055] Example 7

[0056] Zinc chloride and water are mixed in a mass ratio of 1:1.4, and stirred at room temperature until the zinc chloride is completely dissolved, and metal palladium with a mass of 0.08 times the mass of zinc chloride, acetic acid with a mass of 0.7 times the mass of zinc chloride, and hydrochloric acid with a mass of 0.2 times the mass of zinc chloride are added to the mixture; the temperature is raised to 80°C, and refluxed for reaction for 3 hours; a liquid mixture of 29.2wt% zinc chloride, 40.8wt% water, 2.3wt% palladium ions, 20.4wt% acetic acid, and 5.8wt% hydrochloric acid is obtained, and finally 0.05 times the mass of zinc chloride is added to di(triphenylphosphine)copper dichloride to obtain the catalyst CAT3 required for the reaction.

[0057] Vitamin E acetate was prepared by using the continuous phase separation reactor of Examples 1-4 and the catalyst of Examples 5-7:

[0058] Example 8 (S1)

[0059] The reactor described in Example 1 and the catalyst described in Example 5 were used to carry out the reaction experiment. The molar ratio of the reaction raw materials 2,3,5-trimethylhydroquinone diester to isophytol was 1:1.3, n-heptane was selected as the solvent, and the mass ratio of n-heptane to 2,3,5-trimethylhydroquinone diester was 1:1. The three were mixed as the reaction raw materials, and the reaction raw materials entered the reactor at a flow rate of 50.1 kg / h; the catalyst CAT1 entered the reactor at a flow rate of 0.69 kg / h (0.05 times the mass of 2,3,5-trimethylhydroquinone diester), and after filling the catalyst collection area, the catalyst phase was circulated at a flow rate of 0.69 kg / h;

[0060] The reaction temperature is 50°C, the reaction pressure is normal pressure, and the reaction zone adopts internal coils or jackets to transfer heat (both are common heat transfer methods in chemical processes). Since the density of the reaction raw materials is relatively light, they gradually rise after entering the reactor at the bottom. The three reaction zones are similar to three reactors in series; the catalyst has a heavier density and a non-polar hydrophilic composition. It gradually decreases after being added from the upper part of the reactor. The reaction raw materials and the catalyst are fully mixed in the reaction zone. After the upper reaction liquid leaves the reaction zone, it enters the phase separation zone. The oil phase is enriched in the upper part of the phase separation zone. After passing through the pore structure and the lipophilic and hydrophobic filler layer, the catalyst is completely removed and enters the upper reaction liquid collection zone to leave the reactor. After subsequent desolventization, vitamin E acetate that meets the requirements is obtained. After the reaction is stable, the reaction liquid is collected and analyzed.

[0061] The conversion and selectivity were calculated based on 2,3,5-trimethylhydroquinone diester;

[0062] The results showed that the conversion rate of the reaction reached 99.8%, the selectivity reached 98.2%, and the concentrations of metal ions and chloride ions in the reaction solution were less than 1 ppm, respectively. This indicates that isophytol and trimethylhydroquinone diester were fully reacted in the reaction zone, and the reaction products vitamin E acetate, acetic acid, and solvent n-heptane were fully separated in the phase separation zone and the honeycomb channel separation zone, and the catalyst was recycled.

[0063] Example 9 (S2)

[0064] The reactor described in Example 1 and the catalyst described in Example 5 were used to carry out the reaction experiment. The molar ratio of the reaction raw materials 2,3,5-trimethylhydroquinone diester to isophytol was 1:1.3, n-heptane was selected as the solvent, and the mass ratio of n-heptane to 2,3,5-trimethylhydroquinone diester was 1:1. The three were mixed as the reaction raw materials, and the reaction raw materials entered the reactor at a flow rate of 50.1 kg / h; the catalyst CAT1 entered the reactor at a flow rate of 0.276 kg / h (0.02 times the mass of 2,3,5-trimethylhydroquinone diester), and after filling the catalyst collection area, the catalyst phase was circulated at a flow rate of 0.276 kg / h;

[0065] The reaction temperature was 80° C., the reaction pressure was normal pressure, three reaction zones were used, and the catalyst circulation method, reactor heat transfer measures, and reaction liquid collection and analysis were consistent with Example 8.

[0066] The results show that the conversion rate of the reaction reaches 98.7%, the selectivity reaches 98.4%, and the concentrations of metal ions and chloride ions in the reaction solution are less than 0.5 ppm respectively. The conversion rate of this embodiment is lower than that of Example 3, mainly because the catalyst concentration is reduced, the residence time remains unchanged, and the reaction rate decreases; the concentrations of metal ions and chloride ions in the collected reaction solution are reduced, mainly due to the reduction in the amount of catalyst used, and the conversion rate and selectivity of this embodiment are within an acceptable range.

[0067] Embodiment 10 (S3)

[0068] The reactor described in Example 1 and the catalyst described in Example 6 were used to carry out the reaction experiment. The molar ratio of the reaction raw materials 2,3,5-trimethylhydroquinone diester to isophytol was 1:1, n-heptane was selected as the solvent, and the mass ratio of n-heptane to 2,3,5-trimethylhydroquinone diester was 1.2:1. The three were mixed as the reaction raw materials, and the reaction raw materials entered the reactor at a flow rate of 50.1 kg / h; the catalyst CAT2 entered the reactor at a flow rate of 0.725 kg / h (0.05 times the mass of 2,3,5-trimethylhydroquinone diester), and after filling the catalyst collection area, the catalyst phase was circulated at a flow rate of 0.725 kg / h;

[0069] The reaction temperature was 60° C., the reaction pressure was normal pressure, three reaction zones were used, and the catalyst circulation method, reactor heat transfer measures, and reaction liquid collection and analysis were consistent with Example 8.

[0070] The results showed that the conversion rate of the reaction reached 99.2%, the selectivity reached 98.6%, and the concentrations of metal ions and chloride ions in the reaction solution were less than 1 ppm. When the molar ratio of 2,3,5-trimethylhydroquinone diester to isophytol was reduced to 1:1, the reaction could still maintain a high conversion rate and meet the reaction requirements; the change of solvent had little effect on the reaction.

[0071] Example 11 (S4)

[0072] The reactor described in Example 1 and the catalyst described in Example 7 were used to carry out the reaction experiment. The molar ratio of the reaction raw materials 2,3,5-trimethylhydroquinone diester to isophytol was 1:1.3, n-heptane was selected as the solvent, and the mass ratio of n-heptane to 2,3,5-trimethylhydroquinone diester was 1:1. The three were mixed as the reaction raw materials, and the reaction raw materials entered the reactor at a flow rate of 50.1 kg / h; the catalyst CAT3 entered the reactor at a flow rate of 0.69 kg / h (0.05 times the mass of 2,3,5-trimethylhydroquinone diester), and after filling the catalyst collection area, the catalyst phase was circulated at a flow rate of 0.69 kg / h;

[0073] The reaction temperature was 50° C., the reaction pressure was normal pressure, three reaction zones were used, and the catalyst circulation method, reactor heat transfer measures, and reaction liquid collection and analysis were consistent with Example 8.

[0074] The results showed that the conversion rate of the reaction reached 99.6%, the selectivity reached 98.4%, and the concentrations of metal ions and chloride ions in the reaction solution were less than 1.2ppm and 1ppm respectively. The use of CAT2 catalyst still maintained a high conversion rate and selectivity, but the chloride ions and metal ions increased slightly, mainly due to the increase in the chlorine content of the catalyst and the increase in the catalyst residue in the reaction product.

[0075] Embodiment 12 (S5)

[0076] The reaction experiment was carried out using the reactor described in Example 2 and the catalyst described in Example 5;

[0077] The feed conditions and reaction conditions described in Example 8 were adopted, and the operation mode and analysis method were the same.

[0078] The results showed that the conversion rate of the reaction reached 99.5%, the selectivity reached 98.4%, and the concentrations of metal ions and chloride ions in the reaction solution were less than 1 ppm. The reactor described in Example 2 also achieved the desired reaction effect and catalyst separation and recycling purposes.

[0079] Example 13 (S6)

[0080] The reaction experiment was carried out using the reactor described in Example 3 and the catalyst described in Example 5.

[0081] The feed conditions and reaction conditions described in Example 8 were adopted, and the operation mode and analysis method were the same.

[0082] The results show that the conversion rate of the reaction reaches 98.7%, the selectivity reaches 98.6%, and the concentrations of metal ions and chloride ions in the reaction solution are less than 1ppm respectively. The reactor described in Example 3 also achieves the separation of catalyst and reaction solution, the recycling of catalyst and the expected conversion rate and selectivity. The conversion rate of the reaction is slightly reduced, mainly because the reaction zone is reduced and the residence time is reduced, resulting in a decrease in the reaction conversion rate. The change of the bottom baffle does not have a significant effect on the reaction, because the catalyst collected at the bottom returns to the reaction zone for reaction, and the separation requirements of the bottom catalyst are relatively low, and the inclined plate plays a role in the aggregation and sedimentation of the catalyst phase.

[0083] Embodiment 14 (S7)

[0084] The reaction experiment was carried out using the reactor described in Example 4 and the catalyst described in Example 5.

[0085] The feed conditions and reaction conditions described in Example 8 were adopted, and the operation mode and analysis method were the same.

[0086] The results showed that the conversion rate of the reaction reached 99.7%, the selectivity reached 98.4%, and the concentrations of metal ions and chloride ions in the reaction solution were less than 1 ppm. The reactor described in Example 4 also achieved the desired reaction effect and catalyst separation and recycling purposes.

[0087] Comparative Example 1 (S1*)

[0088] The continuous phase-separated reactor of Example 1 was used, and the reaction raw materials and reaction conditions of Example 8 were used, except that no stabilizer or metal palladium was added to the catalyst.

[0089] The results showed that the reaction conversion rate reached 98.4%, the selectivity reached 98.1%, and the concentrations of metal ions and chloride ions in the reaction solution were less than 1 ppm. The reaction conversion rate and selectivity were greatly reduced, and the catalyst did not achieve the expected conversion efficiency; and vitamin E and acetic acid were generated, indicating that the generated vitamin E acetate was hydrolyzed.

[0090] Comparative Example 2 (S2*)

[0091] The continuous phase separation reactor of Example 1 is used, and the reaction raw materials and reaction conditions in Example 8 are used, except that the continuous phase separation reactor does not use a honeycomb-like separation channel, and only provides a filler layer at the bottom of the channel.

[0092] The results showed that the conversion rate of the reaction reached 80.2%, the selectivity reached 86.2%, the metal ion concentration in the reaction solution gradually increased from less than 1ppm at the beginning of the reaction to 320ppm, and the chloride ion concentration increased from 1ppm at the beginning to 240ppm; it was still increasing at the end of the reaction. This shows that the packing layer played an interception role in the initial reaction stage, but as the reaction time increased, too many catalyst droplets reached the packing layer, and the droplets could not be separated by sedimentation in the phase separation zone. After reaching the packing layer, they began to accumulate in the packing layer, and some of them separated and entered the packing layer under the action of the pressure difference, which eventually led to the continuous increase of metal ions and chloride ions in the reaction solution, and the conversion rate and selectivity in the reaction decreased.

[0093] Comparative Example 3 (S3*)

[0094] The continuous phase separation reactor of Example 1 is used, and the reaction raw materials and reaction conditions in Example 8 are used, except that the continuous phase separation reactor does not use a packing layer, and the reaction liquid directly enters the reaction liquid collection area after passing through the pore structure.

[0095] The results show that the reaction conversion rate reaches 84.5%, the selectivity reaches 88.4%, the metal ion concentration in the reaction liquid is 120ppm, and the chloride ion concentration is 68ppm, which are relatively stable. This result shows that the catalyst in the reaction liquid is brought into the reaction liquid, and the metal ions and chloride ions will affect the subsequent products. This is because there are still small catalyst droplets in the reaction liquid after phase separation, which are further separated in the pores. However, since the flow direction of the pores is from bottom to top, some droplets will still be brought into the reaction liquid collection area, and the conversion rate and selectivity of the reaction will decrease.

[0096] Comparative Example 4 (S4*)

[0097] The continuous phase-separation reactor of Example 1 is used, and the reaction raw materials and reaction conditions of Example 8 are used, except that the continuous phase-separation reactor does not use a bottom inclined plate separation structure, and the catalyst directly settles to the bottom for circulation.

[0098] The results showed that the conversion rate of the reaction reached 89.2%, the selectivity reached 99.3%, and the concentration of metal ions and chloride ions in the reaction solution was below 1 ppm. This result shows that the catalyst in the reaction solution did not achieve good aggregation at the bottom, and the catalyst collection area became the reaction area, resulting in a decrease in the concentration of the catalyst circulating in the upper part of the reaction area. When the reaction solution entered the upper reaction area, the conversion rate decreased, and the final reaction did not reach the predetermined conversion rate.

[0099] Table 1 Feed and reaction conditions of Example 8 to Example 14

[0100]

[0101] Table 2 Reaction results of Example 8 to Example 14

[0102] Conversion rate / % Selectivity / % Metal ions / ppm Chloride ion / ppm S1 99.8 98.2 <1 <1 S2 98.7 98.4 <0.5 <0.5 S3 99.2 98.6 <1 <1 S4 99.6 98.4 <1.2 <1.2 S5 99.5 98.4 <1 <1 S6 98.7 98.6 <1 <1 S7 99.7 98.4 <1 <1

[0103] Table 3 Comparative Examples S1*-S4* Conditions and Reaction Results

[0104]

Claims

1. A continuous phase separation reactor, characterized in that: The invention comprises a reaction liquid collecting zone, a honeycomb channel separation zone, a phase separation zone, a plurality of reaction zones, a reaction zone partition, a catalyst separation zone, and a catalyst collecting zone; the top of the reactor is the reaction liquid collecting zone, a reaction liquid outlet is arranged on the outside of the reaction liquid collecting zone, the lower part of the reaction liquid collecting zone is connected to the upper packing layer of the honeycomb channel separation zone, the inlet of the honeycomb channel is connected to the phase separation zone, a plurality of reaction zones are located at the lower part of the phase separation zone, the phase separation zone and the reaction zone are separated by a partition, stirring is arranged in the reaction zone, a reaction raw material inlet and a catalyst inlet are arranged on the outside of the reaction zone, the reaction zones are separated by partitions, the bottom of the reaction zone is connected to the catalyst separation zone, the lower part of the catalyst separation zone is connected to the catalyst collecting zone, and a catalyst outlet is arranged on the outside of the catalyst collecting zone; wherein the catalyst separation zone is composed of an inclined plate with a certain gap, the inclined plate in the catalyst separation zone has an inclination angle of 90-45° to the horizontal plane, the inclined plate gap is 0.02-0.2 times the diameter of the reaction zone, and the height of the inclined plate zone is 0.2-2 times the diameter of the reaction zone.

2. The reactor according to claim 1, characterized in that The catalyst inlet is located at the upper part of the reaction zone, and the reaction raw material inlet is located at the lower part of the reaction zone.

3. The reactor according to claim 1, characterized in that The honeycomb-like channel separation zone has a channel front end connected to the phase separation zone and is composed of honeycomb-like channels, and the channel structure is triangular, square, pentagonal, hexagonal or circular.

4. The reactor according to claim 3, wherein the channel structure of the honeycomb-like channel separation zone is hexagonal or circular.

5. The reactor according to claim 3, wherein the channel structure of the honeycomb-like channel separation zone is hexagonal.

6. The reactor according to claim 3, characterized in that The channel surface comprises plastic or resin with lipophilic and hydrophobic groups, wherein the lipophilic and hydrophobic groups are hydrocarbon groups containing C10-C20, hydrocarbon groups containing polyoxypropylene groups, polysiloxane groups or long-chain perfluoro groups, and hydrocarbon groups containing aromatic groups, amide groups, amine groups, ether bonds, and ester groups.

7. The reactor according to claim 6, characterized in that The lipophilic and hydrophobic groups are hydrocarbon groups containing ester groups and ether bonds.

8. The reactor according to claim 3 or 6, characterized in that The area of ​​a single small channel of the hexagonal channel is 0.001 to 0.1 times the cross-sectional area of ​​the reaction zone, and the length of the channel is 0.5 to 2 times the cross-sectional diameter of the reaction zone.

9. The reactor according to claim 8, characterized in that The area of ​​a single small channel of the hexagonal channel is 0.01 to 0.08 times the cross-sectional area of ​​the reaction zone.

10. The reactor according to claim 8, characterized in that The length of a single small channel of the hexagonal channel is 0.8-1.2 times the cross-sectional diameter of the reaction zone.

11. The reactor according to claim 3, characterized in that The bottom of the hexagonal flow channel is connected to the packing layer, and the packing layer is composed of oleophilic and hydrophobic fibers or oleophilic and hydrophobic particles and activated carbon. The mass ratio of the oleophilic and hydrophobic fibers or oleophilic and hydrophobic particles to the activated carbon is 1: 0.1~1, the height of the packing layer is 0.001-0.2m.

12. The reactor according to claim 11, characterized in that The mass ratio of the oleophilic and hydrophobic fibers or oleophilic and hydrophobic particles to the activated carbon is 1:0.2-0.

5.

13. The reactor according to claim 11, characterized in that The height of the packing layer is 0.005-0.02m.

14. The reactor according to claim 1, characterized in that The reaction zone is a plurality of reaction zones separated by partitions and having circular hole-shaped channels, and the number of the reaction zones is 1 to 10.

15. The reactor according to claim 14, characterized in that The reaction zones are 2-4 reaction zones.

16. The reactor according to claim 1, characterized in that The inclined plate of the catalyst separation zone has an inclination angle of 80-60° to the horizontal plane.

17. The reactor according to claim 1, characterized in that The gap between the inclined plates in the catalyst separation zone is 0.05-0.1 times the diameter of the reaction zone.

18. The reactor according to claim 1, characterized in that The height of the inclined plate area in the catalyst separation zone is 0.3-1.2 times the diameter of the reaction zone.

19. A method for preparing vitamin E acetate, characterized in that: A continuous phase separation reactor according to any one of claims 1 to 18 is used, wherein the catalyst enters from the catalyst inlet; the reaction raw materials, isophytol, 2,3,5-trimethylhydroquinone diester and solvent, enter from the reaction raw material inlet, and after the reactants and the catalyst are fully reacted, the reaction products and the solvent are mainly non-polar lipophilic components, which enter the reaction liquid collection area after separation in the phase separation zone and the honeycomb-like channel at the top of the reactor; the catalyst is mainly a hydrophilic polar component, which enters the catalyst collection area after separation in the catalyst separation zone.

20. The method according to claim 19, characterized in that An external pump circulation system is provided, and the catalyst in the catalyst collection area is circulated to the catalyst feed port of the reaction area through the pump, and then enters the reactor reaction area again for reaction, thereby realizing the reuse of the catalyst.

21. The method according to claim 19, characterized in that The molar ratio of the 2,3,5-trimethylhydroquinone diester to the isophytol is 1:0.8-2.0; and / or the reaction temperature of the reaction is 30-100°C, and the reaction pressure of the reaction is 0-0.5MPaG.

22. The method according to claim 21, characterized in that The molar ratio of the 2,3,5-trimethylhydroquinone diester to the isophytol is 1-1.

3.

23. The method according to claim 21, characterized in that The reaction temperature of the reaction is 40-80°C.

24. The method according to claim 21, characterized in that The reaction pressure of the reaction is 0-0.1 MPaG.

25. The method according to claim 19, characterized in that The solvent used is one or more of C5-C18 straight-chain alkanes, chlorinated alkanes, branched alkanes, ethers or C6-C12 aromatic hydrocarbons; and / or the amount of the solvent used is 0.6-2 times the mass of 2,3,5-trimethylhydroquinone diester.

26. The method according to claim 25, characterized in that The C5-C18 straight-chain alkanes, branched-chain alkanes, chlorinated alkanes and ethers are one or more of n-hexane, n-heptane and petroleum ether.

27. The method according to claim 25, characterized in that The C6-C9 aromatic hydrocarbons are one or more of benzene, ethylbenzene and toluene.

28. The method according to claim 25, characterized in that The amount of the solvent used is 0.8-1.2 times the mass of 2,3,5-trimethylhydroquinone diester.

29. The method according to claim 19, characterized in that The catalyst is a liquid mixture comprising metal halide, water, palladium ions, acetic acid, hydrochloric acid and a stabilizer: 20-65wt% metal halide, 32-41wt% water, 1-11wt% palladium ions, 0.6-21wt% acetic acid, 0.6-7wt% hydrochloric acid and 0.6-7wt% stabilizer.

30. The method according to claim 29, characterized in that The catalyst preparation comprises the following steps: Step 1: Mix the metal halide with water and then add metal palladium, acetic acid and dilute hydrochloric acid; Step 2: Raise the temperature to 50-90°C, reflux for 2-8 hours, and stop the reaction after the metal palladium is completely dissolved; Step 3: Add bis(triphenylphosphine)copper dichloride or bis(triphenylphosphine)ferric dichloride or bis(triphenylphosphine)zinc dichloride as a stabilizer and mix evenly. The added amount is 0.01-0.1 times of the metal halide.

31. The method according to claim 30, characterized in that In the step 1, the mass ratio of metal halide to water is 1:0.5-2, and the mass ratio of metal halide to metal palladium, acetic acid, hydrochloric acid and stabilizer is 1:0.02-0.5:0.01-1:0.01-0.3:0.01-0.

1.

32. The method according to claim 30, characterized in that In the step 2, the reaction temperature is 60-80° C. and the reaction time is 3-5 h.

33. The method according to claim 30, characterized in that The stabilizer in step 3 is bis(triphenylphosphine)zinc dichloride.

34. The method according to claim 30, characterized in that In the step 3, the amount of stabilizer added is 0.01-0.05 times that of the metal halide.

35. The method according to claim 30, characterized in that The metal halide is selected from one or more of cupric chloride, zinc chloride, ferric chloride, palladium chloride and ferrous iodide.

36. The method according to any one of claims 25 to 30, characterized in that The mass of the catalyst used is 0.004-0.09 times the mass of 2,3,5-trimethylhydroquinone diester.

37. The method according to claim 36, characterized in that The mass of the catalyst used is 0.01-0.05 times the mass of 2,3,5-trimethylhydroquinone diester.

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