Method for separating and purifying 4-methyl-1-pentene from mixture containing trans-4-methyl-2-pentene and 1-hexene

Abstract

A method for separating and purifying 4MP1 from a mixture containing 4MTP2 and 1-Hexene comprises the following steps: continuously introducing a solution in which 4MTP2, 1-Hexene and 4MP1 with any concentration are dissolved into a simulated moving bed chromatography system as a raw material solution, collecting a high-purity 4MP1 solution from raffinate of the simulated moving bed chromatography system by adopting a metal organic framework material as a stationary phase, and separating the high-purity 4MP1 solution from the raffinate of the simulated moving bed chromatography system. The extraction liquid is a solution containing impurities 4MTP2 and 1-Hexene. The invention provides a brand new method for separating 4MP1 from 4MTP2 and 1-Hexene, and a complete separation scheme is provided for the prior art; in the separation of high-concentration 4MP1, the relative purity of the separated and purified 4MP1 can reach gt; the recovery rate is gt; and in the separation of low-concentration 4MP1, the rectification level is also exceeded, and the method is more suitable for 4MP1 thermosensitive substances.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of chemical separation technology, and particularly relates to a method for separating and purifying isomer 4-methyl-1-pentene from a mixture of trans-4-methyl-2-pentene and 1-hexene by using simulated moving bed chromatographic separation technology. BACKGROUND

[0002] 4-methyl-1-pentene (4MP1) is an important higher alpha-olefin, which is often used as a monomer to prepare poly(4MP1) (PMP) and other new polymeric materials. PMP has high transparency, superior heat resistance, mechanical properties, electrical properties and drug resistance, and is widely used in the fields of medical devices, electronics and electrical appliances, packaging materials and microporous materials. In the field of medical health, PMP is the core membrane material of the oxygenator in the extracorporeal membrane oxygenation system (ECMO), i.e. "artificial lung". The PMP hollow fiber membrane has high permeability coefficients for O2 and N2, low elution, biological safety, and can achieve better blood gas exchange, solve the problems of plasma leakage and coagulation in clinical practice, and effectively prolong the clinical use time of ECMO, and is recognized as the optimal medium for ECMO. At present, only Membrana Company under 3M Company can exclusively supply this material, forming a monopoly in supply and price, resulting in high ECMO prices. In the field of advanced technology component materials, PMP resin has good heat resistance and easy peeling properties, and can be used as a high-performance release film in the fields of solar cell component materials, flexible printed circuit substrates, AMC (advanced composite materials), display component materials, and high-function rubber sheets. At the same time, the material has low electrical conductivity and the most significant insulation properties, and is very suitable for application in high-frequency fields, and has good application potential in the 5G high-frequency era. At present, this technology is monopolized by Mitsui Chemicals, Inc. of Japan, and the commodity name is TPX.

[0003] At present, the foreign 4MP1 process technology is relatively mature, mainly based on propylene dimerization process such as US2986588, EP083083, Sho58-114736, Sho58-114737, Sho58-114738, etc. The research and improvement direction mainly focuses on improving the selectivity of the catalyst used in the reaction, and the industry technology patent is mainly held by Mitsui Chemicals, Inc. of Japan and Phillips Petroleum Company of the United States. In 2019, the global 4MP1 production was only 21,700 tons. In addition to generating six dimer isomers in the propylene dimerization process, a large amount of trimers is also generated, and the most content impurities are 4MTP2 and 1-Hexene. The commonly used purification method in industry is a series connection of multiple high-level rectifying towers, but 4MP1 is the most unstable high-level alpha-olefin in thermodynamics, and the energy consumption of rectification is high, which is not the most suitable separation means for purifying 4MP1.

[0004] Simulated moving bed chromatography technology (simulated moving bed chromatography) is an important means of continuous production of adsorption separation industry, with the characteristics of producing high purity products and low energy consumption, especially successful in separating drugs and xylene. For example, CN108084007 discloses a method for separating coenzyme Q10 and Q11 by simulated moving bed chromatography, which ensures the purity and biological activity of the product. CN112110787 discloses a technology for separating xylene isomers by using Fe-MOF as filler and simulated moving bed chromatography technology. Compared with batch HPLC industrial chromatography, simulated moving bed chromatography has higher preparation efficiency, lower solvent consumption, and can realize complete separation of low selectivity system. At present, there is no report on the purification of 4MP1 by using simulated moving bed chromatography technology. SUMMARY

[0005] The purpose of the present application is to solve the problems of high energy consumption, product thermal instability and high cost in the purification process of 4MP1. The present application provides a method for separating and purifying 4-methyl-1-pentene (4MP1) from a mixture containing trans-4-methyl-2-pentene (4MTP2) and 1-hexene (1-Hexene), which uses simulated moving bed chromatography technology to separate and purify 4MP1, and meets the requirements of product purity, recovery rate and green production.

[0006] In order to achieve the above technical purpose, the technical scheme of the present application is as follows:

[0007] The present application provides a method for separating and purifying 4-methyl-1-pentene (4MP1) from a mixture containing trans-4-methyl-2-pentene (4MTP2) and 1-hexene (1-Hexene), which includes:

[0008] The solution of 4MTP2, 1-Hexene and 4MP1 with any concentration is continuously fed into the simulated moving bed chromatography system as raw liquid, the stationary phase of the simulated moving bed chromatography system is selected from at least one of Cu-BTC, Mn-dhbq, Fe-dhbq, CAU-10-H, CAU-10-Br, ZIF-7, ZIF-8, ZIF-65, ZIF-67 and ZIF-108 metal organic framework materials, and high-purity 4MP1 solution is collected from the raffinate of the simulated moving bed chromatography system, and the extract is a solution containing impurities 4MTP2 and 1-Hexene.

[0009] Further, the pore size of the metal organic framework material as the stationary phase is between 0.3-0.8nm.

[0010] Further, the stationary phase is selected from at least one of Mn-dhbq, Fe-dhbq, ZIF-8 and ZIF-108.

[0011] Furthermore, the stationary phase metal-organic framework materials involved in this invention can all be obtained using existing techniques.

[0012] As one of the preferred technical solutions, ZIF-108 is prepared by the following method: 2-nitroimidazole and zinc acetate dihydrate are dissolved in N,N-dimethylformamide, stirred and reacted, and washed repeatedly by centrifugation with anhydrous methanol to obtain the purified metal-organic framework material ZIF-108.

[0013] As a preferred technical solution, the ZIF-8 is prepared by the following method: 2-methylimidazole and zinc nitrate hexahydrate are dissolved in methanol, stirred and reacted, and washed repeatedly by centrifugation with anhydrous methanol to obtain the purified metal-organic framework material ZIF-8.

[0014] As a preferred third technical solution, the Mn-dhbq is prepared by the following method: manganese acetate tetrahydrate, 2,5-dihydroxy-1,4-benzoquinone and deionized water are mixed and stirred for 24-48 hours. The purified metal-organic framework material Mn-dhbq is obtained by centrifugation and washing with deionized water multiple times.

[0015] As a preferred fourth technical solution, the Fe-dhbq is prepared by the following method: 2,5-dihydroxy-1,4-benzoquinone and potassium carbonate are added to a 0.023 mol / L aqueous solution of ferrous nitrate heptahydrate to form a precipitate. After the reaction is complete, the sample is repeatedly centrifuged and washed with deionized water until the supernatant becomes completely clear. Then, the supernatant is poured off, and the remaining solid is air-dried naturally in the air to obtain the metal-organic framework material Fe-dhbq.

[0016] Furthermore, the dissolution of 4MTP2, 1-Hexene, and 4MP1 is achieved using an organic solvent selected from at least one of methanol, ethanol, acetonitrile, n-butanol, tetrahydrofuran, isopropanol, n-hexane, n-heptane, n-octane, isooctane, mesitylene, p-diethylbenzene, and triisopropylbenzene; preferably at least one of methanol, ethanol, and isooctane.

[0017] Furthermore, the total concentration of 4MTP2, 1-Hexene and 4MP1 in the raw material solution is 0.01-600 g / L, preferably 1-100 g / L, and more preferably 3-20 g / L.

[0018] Furthermore, the eluent of the simulated moving bed chromatography system is selected from at least one of methanol, ethanol, acetonitrile, n-butanol, tetrahydrofuran, isopropanol, n-hexane, n-heptane, n-octane, isooctane, mesitylene, p-diethylbenzene, and triisopropylbenzene; preferably at least one of methanol, ethanol, and isooctane. Generally, the eluent is selected as the same organic solvent as the feed solution.

[0019] Furthermore, the diameter of the chromatographic column in the simulated moving bed chromatography system is 0.5-500 mm, preferably 0.5-100 mm; the length is 5-1000 mm, preferably 10-100 mm.

[0020] Furthermore, the operating temperature of the simulated moving bed chromatography system is 10-60℃.

[0021] Furthermore, the operating parameters of the simulated moving bed chromatography system are controlled as follows: eluent flow rate 0.1-1000 mL / min, preferably 0.5-100 mL / min, most preferably 1-10 mL / min; feed solution flow rate 0.1-100 mL / min, preferably 0.5-50 mL / min, most preferably 1-10 mL / min; extract flow rate 0.1-100 mL / min, preferably 0.5-50 mL / min, most preferably 1-10 mL / min; raffinate flow rate 1-100 mL / min, preferably 0.5-50 mL / min, most preferably 1-10 mL / min; switching time 0.1-200 min, preferably 1-50 min, most preferably 2-10 min.

[0022] Furthermore, the simulated moving bed chromatography system adopts a 4-zone configuration, wherein the feed solution is injected into the system between zone 2 and zone 3, the raffinate is drawn out between zone 3 and zone 4, the eluent is injected between zone 1 and zone 4, and the extract is drawn out between zone 1 and zone 2.

[0023] Furthermore, the mixture comprising trans-4-methyl-2-pentene (4MTP2) and 1-hexene (1-Hexene) described in this invention is a product of propylene dimerization to prepare 4-methyl-1-pentene. In addition to the main impurities 4MTP2 and 1-Hexene, which are difficult to separate, it also includes small amounts of cis-4-methyl-2-pentene, 2-methyl-2-pentene, 2-methyl-1-pentene, etc.

[0024] Compared with the prior art, the advantages of the present invention are as follows:

[0025] (1) Compared with the current distillation process for separating and purifying 4MP1, simulated moving bed chromatography has lower energy consumption and cost, and can operate within the room temperature range, which is beneficial for the production of the heat-sensitive substance 4MP1. Currently, there is no relevant separation system available for reference. This invention provides a novel method for separating 4MP1 from 4MTP2 and 1-Hexene, providing a complete separation scheme for existing technologies; in the separation of 4MP1 with a concentration of not less than 90%, the relative purity of the separated and purified 4MP1 can reach not less than 99.5 wt%, and the recovery rate is >95 wt%, which is also higher than that of distillation in the separation of low-concentration 4MP1.

[0026] (2) The application adopts metal organic framework material as the stationary phase of simulated moving bed chromatography, has high selectivity for 4MP1, and has higher separation efficiency than common silica gel and resin materials.

[0027] (3) Although the metal organic framework material is not used for the first time as the stationary phase of simulated moving bed chromatography in the application, it is not easy to select a suitable stationary phase for the separation of specific substances. It is necessary to consider whether the pore size distribution of the material matches the molecular cross-sectional size of the substance to be separated, whether there are open metal sites, and whether other specific structures such as cage topology are conducive to separation; whether it is combined with a specific eluent to have excellent separation effect, separation operation conditions, etc., which are all key factors affecting the separation effect. The coupling of all these conditions is not a technical solution that can be determined through a limited number of experiments. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 The operation schematic diagram of the simulated moving bed chromatography used in the application;

[0029] Figure 2 The separation effect of pulse feeding when the separation capacity of the chromatographic column in Example 1 is determined.

[0030] Figure 3 The adsorption isotherm of the chromatographic column when the separation capacity of the chromatographic column in Example 1 is determined. DETAILED DESCRIPTION

[0031] In order to further understand the application, the application provides a method for separating 4MP1, 4MTP2 and 1-Hexene by simulated moving bed chromatography in the following examples, but the application is not limited to these examples. Non-essential improvements and adjustments made by those skilled in the art under the core guiding ideology of the application still fall within the protection scope of the application.

[0032] The simulated moving bed device in the following examples uses a German CESP C9116 (Norr, Germany), as shown in Figure 1 It is equipped with multiple rotary valves and can be connected to 16 chromatographic columns at most. The number of chromatographic columns in each zone is the same, and can be changed within 1-4. It is equipped with 4 S-100 type liquid phase pumps, in which the flow rate of the feed pump is 0-10 mL / min, and the flow rates of the eluent pump, the extract liquid pump and the raffinate liquid pump are 0-50 mL / min. The eluent is injected between zones 4 and 1, the feed liquid is injected between zones 2 and 3, the mixed solution of 4MP1, 4MTP2 and 1-Hexene is collected at the extract liquid outlet between zones 3 and 4, and the high-purity solution of 4MP1 is collected at the raffinate liquid outlet between zones 1 and 2. Every other switching time (the switching time is adjustable), the chromatographic column is switched one position in the opposite direction of the eluent flow.

[0033] The purity and recovery rate of the present application are calculated as follows:

[0034] Purity = weight of 4MP1 in product / total weight of 4MP1, 4MTP2 and 1-Hexene in product * 100%

[0035] Recovery rate = weight of 4MP1 in product / weight of 4MP1 in raw material * 100%

[0036] Example 1

[0037] Preparation of stationary phase and chromatographic column: 2-nitroimidazole and zinc acetate dihydrate (molar ratio of 2-methylimidazole to zinc acetate dihydrate is 2:1) were dissolved in N,N-dimethylformamide, stirred at room temperature for 120 min. After the reaction was completed, the purified metal organic framework material ZIF-108 was obtained by centrifugal washing with anhydrous methanol for multiple times. The purified metal organic framework material was vacuum degassed at 120°C for 24 h to obtain a solvent-removed adsorbent, which was ground to prepare a chromatographic column.

[0038] The pore size of ZIF-108 is 0.3-0.4 nm, and it has a SOD cage-like topology with a large number of polar sites nitro distributed in the channel. This provides the basic conditions for the separation of the three substances.

[0039] First, the separation capacity of the above chromatographic column under methanol as eluent was determined by pulse injection. 20 μL of 4MP1, 4MTP2 and 1-Hexene were injected respectively with methanol as mobile phase, flow rate of 1 mL / min, and detector as differential refractive index detector. The chromatogram is shown in Figure 2 It is shown that 4MP1, 4MTP2 and 1-Hexene have different retention times on the ZIF-108 chromatographic column, and chromatographic separation of 4MP1, 4MTP2 and 1-Hexene can be achieved. Then the liquid adsorption isotherm of the three substances was determined by frontal chromatography. The methanol solution of the three substances with a certain concentration was continuously injected, and the adsorption amount of the chromatographic column for the three substances at different concentrations was determined, as shown in Figure 3 It is shown that 4MP1, 4MTP2 and 1-Hexene have different adsorption amounts on the ZIF-108 chromatographic column, and 4MP1 has the smallest adsorption amount, which can realize the preferential adsorption of impurities 4MP2 and 1-Hexene.

[0040] Separation process:

[0041] The mixture of 4MP1, 4MTP2 and 1-Hexene (4MP1 has a purity of 50% in 4MP1, 4MTP2 and 1-Hexene) was completely dissolved with methanol as mobile phase to prepare a feed solution with a total concentration of 10 g / L.

[0042] The simulated moving bed chromatograph is equipped with 8 chromatographic columns with a size of 1 cm in diameter and 25 cm in length; the stationary phase is ZIF-108; the eluent and the mobile phase are the same, and the operating temperature is 30°C; the operating parameters are determined by optimization as follows: the eluent flow rate is 3.66 mL / min, the feed liquid flow rate is 0.6 mL / min, the extraction liquid flow rate is 3.6 mL / min, the raffinate flow rate is 0.66 mL / min, and the switching time is 6 min. After 64 times of continuous switching, the system reaches equilibrium.

[0043] A solution of high-purity 4MPI is collected from the raffinate outlet, and a solution of 4MTP2 and 1-Hexene is collected from the extract outlet, and gas chromatography analysis shows that the purity of the 4MPI product is 85.4% and the recovery rate is 86.4%.

[0044] Example 2

[0045] The stationary phase and the preparation of the chromatographic column are the same as in Example 1.

[0046] The separation capacity of the chromatographic column under ethanol as the eluent is determined by pulse injection. 20 μL of 4MPI, 4MTP2 and 1-Hexene is injected respectively with ethanol as the mobile phase, and the flow rate is 1 mL / min. The detector is a differential refractive index detector. Then the liquid adsorption isotherm of each of the three substances is determined by front chromatography. The ethanol solution of a certain concentration of the three substances is continuously injected to determine the adsorption amount of the chromatographic column for the three substances at different concentrations.

[0047] Separation process:

[0048] A mixture of 4MPI, 4MTP2 and 1-Hexene (the purity of 4MPI in 4MPI, 4MTP2 and 1-Hexene is 30%) is completely dissolved with ethanol as the mobile phase to prepare a feed liquid with a total concentration of 10 g / L.

[0049] The simulated moving bed chromatograph is equipped with 8 chromatographic columns with a size of 1 cm in diameter and 25 cm in length; the stationary phase is ZIF-108; the eluent and the mobile phase are the same, and the operating temperature is 30°C; the operating parameters are determined by optimization as follows: the eluent flow rate is 3.66 mL / min, the feed liquid flow rate is 0.6 mL / min, the extraction liquid flow rate is 3.6 mL / min, the raffinate flow rate is 0.66 mL / min, and the switching time is 6 min. After 64 times of continuous switching, the system reaches equilibrium.

[0050] A solution of high-purity 4MPI is collected from the raffinate outlet, and a solution of 4MTP2 and 1-Hexene is collected from the extract outlet, and gas chromatography analysis shows that the purity of the 4MPI product is 72.3% and the recovery rate is 84.6%.

[0051] Example 3

[0052] The stationary phase and the preparation of the chromatographic column are the same as in Example 1.

[0053] The separation capacity of the chromatographic column under the condition of isooctane as eluent was determined by pulse injection. 20 μL of 4MP1, 4MTP2 and 1-Hexene were injected respectively with isooctane as mobile phase, the flow rate was 1 mL / min, and the detector was a differential refractive index detector. Then the liquid adsorption isotherms of the three substances were determined by frontal chromatography. The isooctane solutions of the three substances with certain concentrations were continuously injected to determine the adsorption capacity of the chromatographic column for the three substances at different concentrations.

[0054] Separation process:

[0055] The mixture of 4MP1, 4MTP2 and 1-Hexene (the purity of 4MP1 in 4MP1, 4MTP2 and 1-Hexene was 90%) was completely dissolved with isooctane as mobile phase to prepare a feed solution with a total concentration of 10 g / L.

[0056] The simulated moving bed chromatography was equipped with 8 chromatographic columns with a size of 1 cm in diameter and 25 cm in length; the stationary phase was ZIF-108; the eluent and the mobile phase were the same, and the operating temperature was 30°C; the operating parameters were determined by optimization: the flow rate of the eluent was 3.66 mL / min, the flow rate of the feed liquid was 0.6 mL / min, the flow rate of the extract liquid was 3.6 mL / min, the flow rate of the raffinate liquid was 0.66 mL / min, and the switching time was 6 min. After 64 continuous switching, the system reached equilibrium.

[0057] The solution of high-purity 4MP1 was collected from the raffinate outlet, and the solutions of 4MTP2 and 1-Hexene were collected from the extract outlet, and gas chromatography analysis showed that the purity of the 4MP1 product was 99.9%, and the recovery rate was 96.7%.

[0058] Example 4

[0059] Preparation of stationary phase and chromatographic column: 2-methylimidazole and zinc nitrate hexahydrate (the molar ratio of 2-methylimidazole to zinc nitrate hexahydrate was 2:1) were dissolved in methanol, and stirred at room temperature for 120 min. After the reaction was completed, the purified metal organic framework material ZIF-8 was obtained by centrifugal washing with anhydrous methanol for multiple times. The purified metal organic framework material was vacuum degassed at 120°C for 24 h to obtain a solvent-removed adsorbent, which was ground to prepare a chromatographic column.

[0060] The pore size distribution of ZIF-8 was 0.3-0.4 nm, and it had a SOD cage-like topology structure, which provided basic conditions for the separation of the three substances.

[0061] The separation capacity of the chromatographic column under methanol as eluent was determined by pulse injection. 20 μL of 4MP1, 4MTP2 and 1-Hexene was injected respectively with methanol as mobile phase, flow rate 1 mL / min, and detector differential refractive index detector. Then the liquid adsorption isotherm of the three substances was determined by frontal chromatography. The methanol solution of the three substances with certain concentration was continuously injected to determine the adsorption capacity of the chromatographic column to the three substances under different concentrations.

[0062] Separation process:

[0063] The mixture of 4MP1, 4MTP2 and 1-Hexene (4MP1 purity in 4MP1, 4MTP2 and 1-Hexene is 85%) was completely dissolved with methanol as mobile phase to prepare a feed solution with total concentration of 5 g / L.

[0064] The simulated moving bed chromatography was equipped with 8 chromatographic columns with size of 1 cm in diameter and 25 cm in length; the stationary phase was ZIF-8; the eluent and mobile phase were the same, and the operating temperature was 30°C; the operating parameters were determined by optimization: eluent flow rate 6.2 mL / min, feed liquid flow rate 2 mL / min, extractant flow rate 4 mL / min, raffinate flow rate 4.2 mL / min, and switching time 3 min. After 32 times of continuous switching, the system reached equilibrium.

[0065] The solution of high-purity 4MP1 was collected from the raffinate outlet, and the solutions of 4MTP2 and 1-Hexene were collected from the extract outlet, and gas chromatography analysis showed that the purity of 4MP1 product was 98.1% and the recovery rate was 95.1%.

[0066] Example 5

[0067] The stationary phase and the chromatographic column were prepared as in Example 4.

[0068] The separation capacity of the chromatographic column under ethanol as eluent was determined by pulse injection. 20 μL of 4MP1, 4MTP2 and 1-Hexene was injected respectively with ethanol as mobile phase, flow rate 1 mL / min, and detector differential refractive index detector. Then the liquid adsorption isotherm of the three substances was determined by frontal chromatography. The ethanol solution of the three substances with certain concentration was continuously injected to determine the adsorption capacity of the chromatographic column to the three substances under different concentrations.

[0069] Separation process:

[0070] The mixture of 4MP1, 4MTP2 and 1-Hexene (4MP1 purity in 4MP1, 4MTP2 and 1-Hexene is 97%) was completely dissolved with ethanol as mobile phase to prepare a feed solution with total concentration of 5 g / L.

[0071] The simulated moving bed chromatograph is equipped with 8 chromatographic columns with a size of 1 cm in diameter and 25 cm in length; the stationary phase is ZIF-8; the eluent and the mobile phase are the same, and the operating temperature is 30 DEG C; the operating parameters are determined by optimization as follows: the eluent flow rate is 3 mL / min, the feed liquid flow rate is 1.1 mL / min, the extract liquid flow rate is 2 mL / min, the raffinate liquid flow rate is 2.1 mL / min, and the switching time is 3 min. After 16 times of continuous switching, the system reaches equilibrium.

[0072] The solution of high-purity 4MPI is collected from the raffinate liquid outlet, and the solution of 4MTP2 and 1-Hexene is collected from the extract liquid outlet, and gas chromatography analysis shows that the purity of the 4MPI product is 98.3%, and the recovery rate is 97.2%.

[0073] Example 6

[0074] The stationary phase and the preparation of the chromatographic column are the same as in Example 4.

[0075] The separation capacity of the chromatographic column under isooctane as the eluent is determined by pulse injection. Isooctane is used as the mobile phase, and 20 μL of 4MPI, 4MTP2 and 1-Hexene is injected respectively, the flow rate is 1 mL / min, and the detector is a differential refractive index detector. Then the liquid adsorption isotherm of the three substances is determined by using the front chromatography method. The isooctane solution of the three substances with a certain concentration is continuously injected, and the adsorption capacity of the chromatographic column for the three substances under different concentrations is determined.

[0076] Separation process:

[0077] The mixture of 4MPI, 4MTP2 and 1-Hexene (the purity of 4MPI in 4MPI, 4MTP2 and 1-Hexene is 95%) is completely dissolved with isooctane as the mobile phase, and the total concentration of the feed liquid is 5 g / L.

[0078] The simulated moving bed chromatograph is equipped with 8 chromatographic columns with a size of 1 cm in diameter and 25 cm in length; the stationary phase is ZIF-8; the eluent and the mobile phase are the same, and the operating temperature is 30 DEG C; the operating parameters are determined by optimization as follows: the eluent flow rate is 3 mL / min, the feed liquid flow rate is 1.1 mL / min, the extract liquid flow rate is 2 mL / min, the raffinate liquid flow rate is 2.1 mL / min, and the switching time is 3 min. After 16 times of continuous switching, the system reaches equilibrium.

[0079] The solution of high-purity 4MPI is collected from the raffinate liquid outlet, and the solution of 4MTP2 and 1-Hexene is collected from the extract liquid outlet, and gas chromatography analysis shows that the purity of the 4MPI product is 99.5%, and the recovery rate is 97.6%.

[0080] Example 7

[0081] Preparation of stationary phase and chromatographic column: 600 mmol of manganese acetate tetrahydrate, 600 mmol of 2,5-dihydroxy-1,4-benzoquinone, 2000 mL of deionized water were mixed and stirred at room temperature for 36 hours. After the reaction was completed, the solid obtained by the reaction was washed with deionized water by centrifugation for several times to obtain the purified metal-organic framework material Mn-dhbq. The purified metal-organic framework material was vacuum degassed at 150°C for 12 hours to obtain a desolvated adsorbent, which was ground to prepare 8 chromatographic columns.

[0082] The pore size distribution of Mn-dhbq is 0.4-0.8 nm, and contains a large number of open metal sites, which is conducive to generating different interaction forces on different adsorbate molecules. This provides a basic condition for the separation of the three substances.

[0083] The separation capacity of the chromatographic column under methanol as eluent was determined by pulse injection. 20 μL of 4MP1, 4MTP2 and 1-Hexene was injected respectively, the flow rate was 1 mL / min, and the detector was a differential refractive index detector. Then the liquid adsorption isotherm of the three substances was determined by front chromatography. A certain concentration of methanol solution of the three substances was continuously injected, and the adsorption amount of the chromatographic column for the three substances at different concentrations was determined.

[0084] Separation process:

[0085] A mixture of 4MP1, 4MTP2 and 1-Hexene (4MP1 purity in 4MP1, 4MTP2 and 1-Hexene is 60%), was completely dissolved with methanol as mobile phase, and a feed solution with a total concentration of 5 g / L was prepared.

[0086] The simulated moving bed chromatography was equipped with 8 chromatographic columns with a size of 1 cm in diameter and 25 cm in length; the stationary phase was Mn-dhbq; the eluent and the mobile phase were the same, and the operating temperature was 30°C; the operating parameters were optimized and determined as follows: eluent flow rate 3.66 mL / min, feed liquid flow rate 0.6 mL / min, extractant flow rate 3.6 mL / min, raffinate flow rate 0.66 mL / min, and switching time 6 min. After 64 times of continuous switching, the system reached equilibrium.

[0087] A solution of high-purity 4MP1 was collected from the raffinate outlet, and a solution of 4MTP2 and 1-Hexene was collected from the extract outlet, and gas chromatography analysis showed that the purity of the 4MP1 product was 89.4% and the recovery rate was 75.3%.

[0088] Example 8

[0089] The preparation of stationary phase and chromatographic column was the same as that in Example 7.

[0090] The separation capacity of the chromatographic column was determined by pulse injection method using ethanol as eluent. 20 μL of 4MP1, 4MTP2 and 1-Hexene was injected respectively using ethanol as mobile phase at a flow rate of 1 mL / min. The differential refractive index detector was used. Then the liquid adsorption isotherms of the three substances were determined by frontal chromatography. The ethanol solutions of the three substances at a certain concentration were continuously injected to determine the adsorption capacity of the chromatographic column for the three substances at different concentrations.

[0091] Separation process:

[0092] The mixture of 4MP1, 4MTP2 and 1-Hexene (the purity of 4MP1 in 4MP1, 4MTP2 and 1-Hexene was 95%) was completely dissolved using ethanol as mobile phase to prepare a feed solution with a total concentration of 5 g / L.

[0093] The simulated moving bed chromatography was equipped with 8 chromatographic columns with a diameter of 1 cm and a length of 25 cm. The stationary phase was Mn-dhbq. The eluent and mobile phase were the same, and the operating temperature was 30°C. The operating parameters were determined by optimization: the flow rate of eluent was 7.33 mL / min, the flow rate of feed solution was 1.2 mL / min, the flow rate of extractant was 7.2 mL / min, the flow rate of raffinate was 1.33 mL / min, and the switching time was 6 min. After 64 continuous switching, the system reached equilibrium.

[0094] The solution of high-purity 4MP1 was collected from the raffinate outlet, and the solutions of 4MTP2 and 1-Hexene were collected from the extract outlet. Gas chromatography analysis showed that the purity of 4MP1 product was 98.2%, and the recovery rate was 96.3%.

[0095] Example 9

[0096] The stationary phase and the chromatographic column were prepared as in Example 7.

[0097] The separation capacity of the chromatographic column was determined by pulse injection method using isooctane as eluent. 20 μL of 4MP1, 4MTP2 and 1-Hexene was injected respectively using isooctane as mobile phase at a flow rate of 1 mL / min. The differential refractive index detector was used. Then the liquid adsorption isotherms of the three substances were determined by frontal chromatography. The isooctane solutions of the three substances at a certain concentration were continuously injected to determine the adsorption capacity of the chromatographic column for the three substances at different concentrations.

[0098] Separation process:

[0099] The mixture of 4MP1, 4MTP2 and 1-Hexene (the purity of 4MP1 in 4MP1, 4MTP2 and 1-Hexene was 70%) was completely dissolved using isooctane as mobile phase to prepare a feed solution with a total concentration of 5 g / L.

[0100] The simulated moving bed chromatography was equipped with 8 chromatographic columns with a size of 1 cm in diameter and 25 cm in length; the stationary phase was Mn-dhbq; the eluent and mobile phase were the same, and the operating temperature was 30°C; the operating parameters were determined by optimization: eluent flow rate 1.83 mL / min, feed liquid flow rate 0.3 mL / min, extract liquid flow rate 1.8 mL / min, raffinate liquid flow rate 0.33 mL / min, and switching time 3 min. After 64 continuous switching, the system reached equilibrium.

[0101] The solution of high-purity 4MPI was collected from the raffinate liquid outlet, and the solution of 4MTP2 and 1-Hexene was collected from the extract liquid outlet, and gas chromatography analysis showed that the purity of the 4MPI product was 97.6%, and the recovery rate was 94.3%.

[0102] Example 10

[0103] Preparation of stationary phase and chromatographic column: 2,5-dihydroxy-1,4-benzoquinone and potassium carbonate were added to a 0.023 mol / L aqueous solution of ferrous nitrate heptahydrate, and a precipitate was immediately formed. After the reaction was completed, the sample was repeatedly washed by centrifugation with deionized water until the supernatant became completely clear, then the upper clear liquid was poured out, and the remaining solid was naturally air-dried to obtain Fe-dhbq powder. The prepared Fe-dhbq was vacuum degassed at 150°C, ground, and then prepared into 8 chromatographic columns.

[0104] The pore size distribution of Fe-dhbq was 0.4-0.8 nm, and it contained a large number of open metal sites, which was beneficial to produce different interaction forces on different adsorbate molecules. This provided the basic conditions for the separation of the three substances.

[0105] The separation capacity of the chromatographic column under methanol as eluent was determined by pulse injection. 20 μL of 4MPI, 4MTP2 and 1-Hexene was injected respectively with methanol as mobile phase, the flow rate was 1 mL / min, and the detector was a differential refractive index detector. Then the liquid adsorption isotherm of the three substances was determined by frontal chromatography. The methanol solution of the three substances with a certain concentration was continuously injected to determine the adsorption amount of the chromatographic column for the three substances at different concentrations.

[0106] Separation process:

[0107] The mixture of 4MPI, 4MTP2 and 1-Hexene (the purity of 4MPI in 4MPI, 4MTP2 and 1-Hexene was 20%) was completely dissolved with methanol as mobile phase to prepare a feed liquid with a total concentration of 5 g / L.

[0108] The simulated moving bed chromatograph was equipped with 8 chromatographic columns with a size of 1 cm in diameter and 25 cm in length; the stationary phase was Fe-dhbq; the eluent and mobile phase were the same, and the operating temperature was 30 °C; the operating parameters were determined by optimization as follows: eluent flow rate 1.83 mL / min, feed liquid flow rate 0.3 mL / min, extract liquid flow rate 1.8 mL / min, raffinate liquid flow rate 0.33 mL / min, switching time 3 min. After 64 times of continuous switching, the system reached equilibrium.

[0109] A solution of high-purity 4MPI was collected from the raffinate outlet, and a solution of 4MTP2 and 1-Hexene was collected from the extract outlet, and gas chromatography analysis showed that the purity of the 4MPI product was 50.4%, and the recovery rate was 75.3%.

[0110] Example 11

[0111] The stationary phase and the preparation of the chromatographic column were the same as in Example 10.

[0112] The separation capacity of the chromatographic column under ethanol as the eluent was determined by pulse injection. 20 μL of 4MPI, 4MTP2 and 1-Hexene was injected respectively with ethanol as the mobile phase, and the flow rate was 1 mL / min. The detector was a differential refractive index detector. Then the liquid adsorption isotherm of the three substances was determined by frontal chromatography. The ethanol solution of the three substances with a certain concentration was continuously injected to determine the adsorption amount of the chromatographic column for the three substances at different concentrations.

[0113] Separation process:

[0114] A mixture of 4MPI, 4MTP2 and 1-Hexene (the purity of 4MPI in 4MPI, 4MTP2 and 1-Hexene was 85%) was completely dissolved with ethanol as the mobile phase to prepare a feed liquid with a total concentration of 5 g / L.

[0115] The simulated moving bed chromatograph was equipped with 8 chromatographic columns with a size of 1 cm in diameter and 25 cm in length; the stationary phase was Fe-dhbq; the eluent and mobile phase were the same, and the operating temperature was 30 °C; the operating parameters were determined by optimization as follows: eluent flow rate 2.2 mL / min, feed liquid flow rate 5.4 mL / min, extract liquid flow rate 2.3 mL / min, raffinate liquid flow rate 5.3 mL / min, switching time 3 min. After 64 times of continuous switching, the system reached equilibrium.

[0116] A solution of high-purity 4MPI was collected from the raffinate outlet, and a solution of 4MTP2 and 1-Hexene was collected from the extract outlet, and gas chromatography analysis showed that the purity of the 4MPI product was 97.8%, and the recovery rate was 95.6%.

[0117] Example 12

[0118] The stationary phase and the preparation of the column are the same as in Example 10.

[0119] The separation capacity of the column was determined by pulse injection method using isooctane as eluent. 20 μL of 4MP1, 4MTP2 and 1-Hexene were injected respectively using isooctane as mobile phase at a flow rate of 1 mL / min, and a differential refractive index detector was used. Then the liquid adsorption isotherms of the three substances were determined by frontal chromatography. The isooctane solutions of the three substances at certain concentrations were continuously injected to determine the adsorption capacity of the column for the three substances at different concentrations.

[0120] Separation process:

[0121] A mixture of 4MP1, 4MTP2 and 1-Hexene (4MP1 purity in 4MP1, 4MTP2 and 1-Hexene is 95%) was completely dissolved using isooctane as mobile phase to prepare a feed solution with a total concentration of 5 g / L.

[0122] The simulated moving bed chromatography was equipped with 8 columns with a diameter of 1 cm and a length of 25 cm, and the stationary phase was Fe-dhbq. The eluent and the mobile phase were the same, and the operating temperature was 30°C. The operating parameters were determined by optimization: eluent flow rate 1.83 mL / min, feed flow rate 0.3 mL / min, extractant flow rate 1.8 mL / min, raffinate flow rate 0.33 mL / min, and switching time 3 min. After 64 continuous switching, the system reached equilibrium.

[0123] The solution of high-purity 4MP1 was collected from the raffinate outlet, and the solutions of 4MTP2 and 1-Hexene were collected from the extract outlet. Gas chromatography analysis showed that the purity of the 4MP1 product was 98.4%, and the recovery rate was 96.5%.

[0124] Comparative Example 1

[0125] The traditional rectification separation method of the prior art:

[0126] A mixture of 4MP1, 4MTP2 and 1-Hexene (4MP1 purity in 4MP1, 4MTP2 and 1-Hexene is 90%) was used as raw material to enter the rectification column for separation. The number of plates of the rectification column was 70-80, and the operating temperature was 65°C. The bottom kettle liquid was 4MTP2 and 1-Hexene, and the 4- methyl-1-pentene rectification column top was the finally separated 4MP1, and the purity was measured to be 98.5%, and the recovery rate was 80%. However, the whole process had high energy consumption, high equipment investment cost, and large product loss.

Claims

1. A method for separating and purifying 4MP1 from a mixture comprising 4MTP2 and 1-Hexene, comprising: continuously feeding a solution of 4MTP2, 1-Hexene and 4MP1 dissolved in any concentration as a feed liquid into a simulated moving bed chromatography system, the stationary phase of the simulated moving bed chromatography system being selected from at least one of Cu-BTC, Mn-dhbq, Fe-dhbq, CAU-10-H, CAU-10-Br, ZIF-7, ZIF-8, ZIF-65, ZIF-67 and ZIF-108 metal organic framework materials, collecting a high-purity 4MP1 solution from the raffinate of the simulated moving bed chromatography system, and the extract being a solution containing impurities 4MTP2 and 1-Hexene.

2. The method of claim 1, wherein, The stationary phase is selected from at least one of Mn-dhbq, Fe-dhbq, ZIF-8 and ZIF-108.

3. The method of claim 1, wherein, The 4MTP2, 1-Hexene and 4MP1 are dissolved using an organic solvent, the organic solvent being selected from at least one of methanol, ethanol, acetonitrile, n-butanol, tetrahydrofuran, isopropanol, n-hexane, n-heptane, n-octane, isooctane, mesitylene, p-diethylbenzene and triisopropylbenzene.

4. The method of claim 1, wherein, The total concentration of 4MTP2, 1-Hexene and 4MP1 in the feed liquid is 0.01-600 g / L.

5. The method of claim 1, wherein, The eluent of the simulated moving bed chromatography system is selected from at least one of methanol, ethanol, acetonitrile, n-butanol, tetrahydrofuran, isopropanol, n-hexane, n-heptane, n-octane, isooctane, mesitylene, p-diethylbenzene and triisopropylbenzene.

6. The method of claim 1, wherein, The diameter of the chromatographic column of the simulated moving bed chromatography system is 0.5-500 mm, and the length is 5-1000 mm.

7. The method of claim 1, wherein, The operating temperature of the simulated moving bed chromatography system is 10-60 °C.

8. The method of claim 1, wherein, The operating parameters of the simulated moving bed chromatography system are controlled as follows: the flow rate of the eluent is 0.1-1000 mL / min, the flow rate of the feed liquid is 0.1-100 mL / min, the flow rate of the extract is 0.1-100 mL / min, the flow rate of the raffinate is 1-100 mL / min, and the switching time is 0.1-200 min.

9. The method of claim 8, wherein, The operating parameters of the simulated moving bed chromatography system are controlled as follows: the flow rate of the eluent is 0.5-100 mL / min, the flow rate of the feed liquid is 0.5-50 mL / min, the flow rate of the extract is 0.5-50 mL / min, the flow rate of the raffinate is 0.5-50 mL / min, and the switching time is 1-50 min.

10. The method of claim 1, wherein, The simulated moving bed chromatography system is operated in a 4-zone mode, wherein the feed liquid is injected into the system between zones 2 and 3, the raffinate is led out between zones 3 and 4, the eluent is injected between zones 1 and 4, and the extract is led out between zones 1 and 2.

11. The method of claim 2, wherein, The ZIF-108 is prepared by the following method: 2-nitroimidazole and zinc acetate dihydrate are dissolved in N,N-dimethylformamide, the reaction is stirred, and the purified metal organic framework material ZIF-108 is obtained by centrifugal washing with anhydrous methanol for multiple times.

12. The method of claim 2, wherein, The ZIF-8 is prepared by dissolving 2-methylimidazole and zinc nitrate hexahydrate in methanol, stirring the reaction, and washing the purified metal organic framework material ZIF-8 by centrifugation with anhydrous methanol for multiple times.

13. The method of claim 2, wherein, The Mn-dhbq is prepared by mixing manganese acetate tetrahydrate, 2,5-dihydroxy-1,4-benzoquinone, and deionized water, stirring the reaction for 24-48 hours, and washing the purified metal organic framework material Mn-dhbq by centrifugation with deionized water for multiple times.

14. The method of claim 2, wherein, The Fe-dhbq is prepared by adding 2,5-dihydroxy-1,4-benzoquinone and potassium carbonate to an aqueous solution of ferrous nitrate heptahydrate at a concentration of 0.023 mol / L, forming a precipitate, and, after the reaction is completed, repeatedly centrifuging and washing with deionized water until the supernatant of the washed sample becomes completely clear, after which the supernatant is poured off, and the remaining solid is air-dried, to obtain the metal organic framework material Fe-dhbq.

15. The method of claim 1, wherein, The mixture comprising 4MTP2 and 1-Hexene is the product of dimerization of propylene to 4-methyl-1-pentene.

Images