An in-situ hydrophobic supramolecular system for separating and purifying aconitic acid and a method for separating and purifying aconitic acid

Abstract

The application discloses an in-situ hydrophobic supramolecular system for separating and purifying aconitic acid and a method for separating and purifying aconitic acid, relates to the technical field of aconitic acid separation and purification, and the in-situ hydrophobic supramolecular system comprises a hydrogen bond acceptor neutral amine which is hardly soluble in water and a diluent, and the diluent is one or more of n-hexanol, n-octanol, 2-octanol, isopentyl ether, n-hexyl ether and the like. Therefore, the application provides the in-situ hydrophobic supramolecular system for separating and purifying aconitic acid and the method for separating and purifying aconitic acid, the in-situ hydrophobic supramolecular system has the advantages of good stability, high recovery rate and easy recycling, and the like, the aconitic acid product prepared by the method has high yield and high purity, the method is simple, effective, green, energy-saving, environment-friendly and the like.

Description

Technical Field

[0001] This application relates to the field of aconitic acid purification and separation technology, and in particular to an in-situ hydrophobic supramolecular system for separating and purifying aconitic acid and a method for separating and purifying aconitic acid. Background Technology

[0002] Aconitic acid is an unsaturated tricarboxylic acid that exhibits cis-trans isomerism, existing as cis-aconitic acid and trans-aconitic acid. These two isomers can interconvert; cis-aconitic acid hydrolyzes in cold water to form cis-aconitic acid, which then rearranges back to trans upon heating. Trans-aconitic acid is a plant defense metabolite.

[0003] In the future, bio-based aconitic acid may become a mainstream product in the market. As a chemical product, trans-aconitic acid has wide applications in food, pesticides, medical materials, plastics, and chemicals. In the pesticide field, trans-aconitic acid has good nematode control activity, inhibiting or killing sweet potato stem nematodes, soybean cyst nematodes, southern root-knot nematodes, and cotton bollworms, and is used in the research and development of new nematicidal biological pesticides. In the chemical field, trans-aconitic acid is also used as a raw material for the production of antibacterial agents, antioxidants, plasticizers, lubricants, and other chemical raw materials.

[0004] Trans-aconitate is a new generation of bio-based green plasticizers, characterized by excellent performance, diverse functions, and environmental friendliness. With increasingly stringent environmental regulations, trans-aconitate is expected to gradually replace traditional phthalate plasticizers, contributing to the high-quality, green, and low-carbon development of industries such as packaging, construction, and chemicals. While trans-aconitate has great application potential, technological limitations have prevented large-scale, low-cost production, thus restricting its market development. In recent years, with breakthroughs in aconitate fermentation technology achieved by the Qingdao Institute of Energy, aconitate has gradually achieved mass production in China. In the future, bio-based trans-aconitate may gradually replace petroleum-based trans-aconitate as the mainstream product in the market.

[0005] Despite the huge potential market for aconitic acid, its large-scale industrial application is currently limited by the high cost of separation and purification, which has become a bottleneck for its promotion and application. The method provided by this invention efficiently solves the problem of aconitic acid production, improves the separation and purification efficiency of aconitic acid, and helps to rapidly promote its industrialization. Summary of the Invention

[0006] The purpose of this application is to provide an in-situ hydrophobic supramolecular system for separating and purifying aconitic acid and a method for separating and purifying aconitic acid, thereby solving the technical problems of high purification cost and low purification efficiency in the prior art.

[0007] This application provides an in-situ hydrophobic supramolecular system for separating and purifying aconitic acid. The in-situ hydrophobic supramolecular system includes a water-insoluble hydrogen bond acceptor neutral amine and a diluent. The diluent is one or more organic solvents selected from n-hexanol, n-octanol, 2-octanol, isopentyl ether, and n-hexyl ether.

[0008] Preferably, the water-insoluble hydrogen bond acceptor neutral amine is a hydrophobic triamine with the molecular formula R1R2N(CH2). n NR(CH2) n CONR3R4, R1, R2, R3, R4 are C3-C 10 One or more of the following, where R is H or C1-C 10 Alkyl groups; hydrocarbon groups in which n is one or more of 1, 2 or 3.

[0009] Preferably, the volume ratio of the water-insoluble hydrogen bond acceptor neutral amine to the diluent is (0.1-10):1.

[0010] This application provides a method for separating and purifying aconitic acid, comprising the following steps:

[0011] S1. Mix water-insoluble hydrogen bond acceptor neutral amines with diluents at a volume ratio of (0.1-10):1 to obtain an in-situ hydrophobic supramolecular system for separating and purifying aconitic acid.

[0012] S2. Mix the in-situ hydrophobic supramolecular system obtained in S1 with the fermentation broth containing aconitic acid, so that the aconitic acid associates with the in-situ hydrophobic supramolecular system to obtain a hydrophobic supramolecular system with associated aconitic acid.

[0013] S3. Wash the hydrophobic supramolecular associated with aconitic acid with detergent to purify and remove impurities from the hydrophobic supramolecular associated with aconitic acid.

[0014] S4. The purified aconitic hydrophobic supramolecular associating with aconitic acid obtained in step S3 is mixed with the desorbing agent and heated to destroy the internal forces of the aconitic acid and hydrophobic supramolecular system, thereby obtaining the hydrophobic supramolecular and the desorbed high-purity aconitic acid solution; the high-purity aconitic acid solution is then deoiled, decolorized, concentrated and crystallized to obtain the aconitic acid solid product.

[0015] S5. The hydrophobic supramolecular obtained in step S4 is thoroughly mixed with the purifying agent. The hydrophobic supramolecular reacts fully with the purifying agent to remove residual impurities from the hydrophobic supramolecular. It is then further associated with the aconitic acid fermentation broth to prepare aconitic acid-containing hydrophobic supramolecular.

[0016] 5. The method for separating and purifying aconitine according to claim 4, characterized in that, in step S2, the volume ratio of the in-situ hydrophobic supramolecular molecules to the aconitine fermentation broth is (1-5):1.

[0017] Preferably, in step S4, the volume ratio of the purified hydrophobic supramolecular aconitine to the desorbent is (1-5):1.

[0018] Preferably, the detergent is a mixture of aconitic acid and sodium aconitic acid.

[0019] Preferably, the eluent is sodium hydroxide, sodium aconitate, or water, and the concentration of the eluent is (0-3) mol / L.

[0020] Preferably, the purifying agent is an alkaline solution.

[0021] Therefore, the above-mentioned in-situ hydrophobic supramolecular system and method for separating and purifying aconitic acid have the following beneficial effects:

[0022] (1) High separation efficiency, the residual concentration of aconitic acid in the original solution after separation and purification is less than 2%;

[0023] (2) It has strong selectivity, separating only aconitic acid and substances with the same polarity, without separating other substances;

[0024] (3) Low production cost, since the separation and purification are carried out under normal pressure, no other raw and auxiliary materials are required;

[0025] (4) It has high separation selectivity, forming a hydrophobic supramolecular system only with aconitine and substances with the same polarity, resulting in stable product quality and a product purity of 99%.

[0026] (5) It can be operated continuously, and the hydrophobic supramolecular system can be recycled for separation and purification after analysis and purification, reducing production and operating costs. No waste is generated in the production process, which is conducive to ecological stability. This method is low-cost, high-quality, and environmentally friendly, and has great application prospects and potential. Detailed Implementation

[0027] Example 1

[0028] A method for separating and purifying aconitic acid includes the following steps:

[0029] (1) Preparation of in-situ hydrophobic supramolecular system: CH3CH2CH2N(CH3CH2CH2)CH2NHCH2CON(CH3CH2CH2)2 with a volume ratio of 3:7 was mixed with isopentyl ether to prepare in-situ hydrophobic supramolecular system.

[0030] (2) In-situ hydrophobic supramolecular system associated with aconitic acid: The in-situ hydrophobic supramolecular system of step (1) was mixed with aconitic acid solution at a volume ratio of 3:1, stirred at 30°C for 3 min, and allowed to stand for phase separation; the in-situ hydrophobic supramolecular system associated with aconitic acid was obtained, the concentration of aconitic acid remaining in the fermentation broth was 0.6 g / L, and the aconitic acid association rate was 98.3%;

[0031] (3) Purify the hydrophobic supramolecular system of associated aconitine: Mix the in-situ hydrophobic supramolecular system of associated aconitine obtained in step (2) with the aconitine solution at a volume ratio of 30:1 and wash. Stir at 30°C for 3 min to remove impurities from the hydrophobic supramolecular system of associated aconitine.

[0032] (4) Desorption of hydrophobic supramolecular aconitic acid: The purified hydrophobic supramolecular aconitic acid obtained in step (3) was mixed with a 3 mol / L aqueous solution of sodium hydroxide and sodium aconitate at a volume ratio of 2:1. The mixture was stirred at 80°C for 3 min to break the internal forces of the hydrophobic supramolecular aconitic acid, and the aconitic acid was transferred to hot water. After decolorization, concentration and crystallization, solid aconitic acid product was obtained. The single-step desorption rate was 66.2%, and after multiple desorptions, the concentration of the eluent was 130 g / L, with a yield of 99.2%.

[0033] (5) Purify the hydrophobic supramolecular system after aconitic acid analysis: Mix the hydrophobic supramolecular system after analysis in step (4) with sodium hydroxide solution at a volume ratio of 10:1, stir at 80°C for 3 min to purify the hydrophobic supramolecular system, and its acid content is less than 0.1 g / L. Then, continue to associate with the fermentation broth containing aconitic acid to prepare hydrophobic supramolecular system containing aconitic acid for recycling.

[0034] Example 2

[0035] A method for separating and purifying aconitic acid includes the following steps:

[0036] (1) Preparation of in-situ hydrophobic supramolecular system: CH3CH2CH2N(CH3CH2CH2)CH2N(CH3CH2)CH2CON(CH3CH2CH2)2 with n-hexanol in a volume ratio of 10:1 was mixed to prepare an in-situ hydrophobic supramolecular system.

[0037] (2) In-situ hydrophobic supramolecular system associated with aconitic acid: The in-situ hydrophobic supramolecular system of step (1) was mixed with aconitic acid solution at a volume ratio of 1:1, stirred at 30°C for 3 min, and allowed to stand for phase separation; the in-situ hydrophobic supramolecular system associated with aconitic acid was obtained, the concentration of aconitic acid remaining in the fermentation broth was 0.2 g / L, and the aconitic acid association rate was 99.1%;

[0038] (3) Purify the hydrophobic supramolecular system of associated aconitine: Mix the in-situ hydrophobic supramolecular system of associated aconitine obtained in step (2) with the aconitine solution at a volume ratio of 30:1 and wash. Stir at 30°C for 3 min to remove impurities from the hydrophobic supramolecular system of associated aconitine.

[0039] (4) Desorption of hydrophobic supramolecular aconitic acid: The purified hydrophobic supramolecular aconitic acid obtained in step (3) was mixed with a 2 mol / L aqueous solution of sodium hydroxide and sodium aconitate at a volume ratio of 1:1. The mixture was stirred at 80°C for 3 min to break the internal forces of the hydrophobic supramolecular aconitic acid, and the aconitic acid was transferred to hot water. After decolorization, concentration and crystallization, solid aconitic acid product was obtained. The single-step desorption rate was 76.2%, and after multiple desorptions, the concentration of the eluent was 145 g / L, with a yield of 99.2%.

[0040] (5) Purify the hydrophobic supramolecular system after aconitic acid analysis: Mix the hydrophobic supramolecular system after analysis in step (4) with sodium hydroxide solution at a volume ratio of 10:1, stir at 80°C for 3 min to purify the hydrophobic supramolecular system, and its acid content is less than 0.1 g / L. Then continue to associate with the fermentation broth containing aconitic acid to prepare hydrophobic supramolecular system containing aconitic acid for recycling.

[0041] Example 3

[0042] A method for separating and purifying aconitic acid includes the following steps:

[0043] (1) Preparation of in-situ hydrophobic supramolecular system: CH3CH2CH2CH2CH2N(CH3CH2CH2CH2)CH2N(CH3CH2)CH2CON(CH3CH2CH2CH2)2 with a volume ratio of 0.1:1 was mixed with n-octanol to prepare an in-situ hydrophobic supramolecular system.

[0044] (2) In-situ hydrophobic supramolecular system associated with aconitic acid: The in-situ hydrophobic supramolecular system of step (1) was mixed with aconitic acid solution at a volume ratio of 5:1, stirred at 30°C for 3 min, and allowed to stand for phase separation; the in-situ hydrophobic supramolecular system associated with aconitic acid was obtained, the concentration of aconitic acid remaining in the fermentation broth was 0.8 g / L, and the aconitic acid association rate was 98.5%;

[0045] (3) Purify the hydrophobic supramolecular system of associated aconitine: Mix the in-situ hydrophobic supramolecular system of associated aconitine obtained in step (2) with the aconitine solution at a volume ratio of 30:1 and wash. Stir at 30°C for 3 min to remove impurities from the hydrophobic supramolecular system of associated aconitine.

[0046] (4) Desorption of hydrophobic supramolecular aconitic acid: The purified hydrophobic supramolecular aconitic acid obtained in step (3) was mixed with a 3 mol / L aqueous solution of sodium hydroxide and sodium aconitate at a volume ratio of 5:1. The mixture was stirred at 80°C for 3 min to break the internal forces of the hydrophobic supramolecular aconitic acid, and the aconitic acid was transferred to hot water. After decolorization, concentration and crystallization, solid aconitic acid product was obtained. The single-step desorption rate was 72.9%, and after multiple desorptions, the concentration of the eluent was 132.2 g / L, with a yield of 99.0%.

[0047] (5) Purify the hydrophobic supramolecular system after aconitic acid analysis: Mix the hydrophobic supramolecular system after analysis in step (4) with sodium hydroxide solution at a volume ratio of 10:1, stir at 80°C for 3 min to purify the hydrophobic supramolecular system, and its acid content is less than 0.1 g / L. Then continue to associate with the fermentation broth containing aconitic acid to prepare hydrophobic supramolecular system containing aconitic acid for recycling.

[0048] Comparative Example 1

[0049] (1) Preparation of in-situ hydrophobic supramolecular system: CH3CH2CH2CH2CH2N(CH3CH2CH2CH2)CH2N(CH3CH2)CH2CON(CH3CH2CH2CH2)2 with a volume ratio of 0.09:1 was mixed with n-octanol to prepare an in-situ hydrophobic supramolecular system.

[0050] (2) In-situ hydrophobic supramolecular system associated with aconitic acid: The in-situ hydrophobic supramolecular system obtained in step (1) was mixed with aconitic acid solution at a volume ratio of 5:1, stirred at 30°C for 3 min, and allowed to stand for phase separation; the in-situ hydrophobic supramolecular system associated with aconitic acid was obtained, the concentration of aconitic acid remaining in the fermentation broth was 1.1 g / L, and the aconitic acid association rate was 97.7%;

[0051] (3) Purify the hydrophobic supramolecular system of associated aconitine: Mix the in-situ hydrophobic supramolecular system of associated aconitine obtained in step (2) with the aconitine solution at a volume ratio of 30:1 and wash. Stir at 30°C for 3 min to remove impurities from the hydrophobic supramolecular system of associated aconitine.

[0052] (4) Desorption of hydrophobic supramolecular aconitic acid: The purified hydrophobic supramolecular aconitic acid obtained in step (3) was mixed with a 3 mol / L aqueous solution of sodium hydroxide and sodium aconitate at a volume ratio of 5:1. The mixture was stirred at 80℃ for 3 min to break the internal forces of the hydrophobic supramolecular aconitic acid, and the aconitic acid was transferred to hot water. After decolorization, concentration and crystallization, solid aconitic acid product was obtained. The single-step desorption rate was 82.1%, and after multiple desorptions, the concentration of the eluent was 137.2 g / L, with a yield of 99.4%.

[0053] (5) Purify the hydrophobic supramolecular system after aconitic acid analysis: Mix the hydrophobic supramolecular system after analysis in step (4) with sodium hydroxide solution at a volume ratio of 10:1, stir at 80°C for 3 min to purify the hydrophobic supramolecular system, and its acid content is less than 0.1 g / L. Then continue to associate with the fermentation broth containing aconitic acid to prepare hydrophobic supramolecular system containing aconitic acid for recycling.

[0054] Comparative Example 2

[0055] (1) Preparation of in-situ hydrophobic supramolecular system: CH3CH2CH2N(CH3CH2CH2)CH2N(CH3CH2)CH2CON(CH3CH2CH2)2 with n-hexanol in a volume ratio of 11:1 was mixed to prepare an in-situ hydrophobic supramolecular system.

[0056] (2) In-situ hydrophobic supramolecular system associated with aconitic acid: The in-situ hydrophobic supramolecular system obtained in step (1) was mixed with aconitic acid solution at a volume ratio of 1:1, stirred at 30°C for 3 min, and allowed to stand for phase separation; the in-situ hydrophobic supramolecular system associated with aconitic acid was obtained, the concentration of aconitic acid remaining in the fermentation broth was 1.5 g / L, and the aconitic acid association rate was 96.2%;

[0057] (3) Purify the hydrophobic supramolecular system of associated aconitine: Mix the in-situ hydrophobic supramolecular system of associated aconitine obtained in step (2) with the aconitine solution at a volume ratio of 30:1 and wash. Stir at 30°C for 3 min to remove impurities from the hydrophobic supramolecular system of associated aconitine.

[0058] (4) Desorption of hydrophobic supramolecular aconitic acid: The purified associated hydrophobic supramolecular aconitic acid obtained in step (3) was mixed with a 2 mol / L aqueous solution of sodium hydroxide and sodium aconitate at a volume ratio of 1:1. The mixture was stirred at 80℃ for 3 min to break the internal forces of the associated hydrophobic supramolecular aconitic acid, and the aconitic acid was transferred to hot water. After decolorization, concentration and crystallization, aconitic acid solid product was obtained. The single-step desorption rate was 61.8%, and after multiple desorptions, the concentration of the eluent was 137.4 g / L, with a yield of 98.2%.

[0059] (5) Purify the hydrophobic supramolecular system after aconitic acid analysis: Mix the hydrophobic supramolecular system after analysis in step (4) with sodium hydroxide solution at a volume ratio of 10:1, stir at 80°C for 3 min to purify the hydrophobic supramolecular system, and its acid content is less than 0.1 g / L. Then continue to associate with the fermentation broth containing aconitic acid to prepare hydrophobic supramolecular system containing aconitic acid for recycling.

[0060] By comparing the proportions, it was found that if the volume ratio of the original hydrophobic supramolecular to the diluent was too high or too low, the aconitic acid association rate would decrease, which would not meet the requirements of this method.

[0061] Therefore, this invention provides an in-situ hydrophobic supramolecular system for separating and purifying aconitic acid, as well as a method for separating and purifying aconitic acid. The in-situ hydrophobic supramolecular system has advantages such as good stability, high recovery rate, and easy recycling. The method yields aconitic acid products with high yield and high purity. The method is simple and effective, and the process is green, energy-saving, and environmentally friendly.

[0062] In the description of this specification, references to terms such as "an experimental example," "example," or "specific example" indicate that a specific feature, structure, material, or characteristic described in connection with that experimental example or example is included in at least one experimental example or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same experimental example or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more experimental examples or examples.

[0063] Finally, it should be noted that the above experimental examples are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred experimental examples, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. An in-situ hydrophobic supramolecular system for the separation and purification of aconitic acid, characterized in that, The in-situ hydrophobic supramolecular system includes water-insoluble hydrogen bond acceptor neutral amines and diluents, wherein the diluents are one or more organic solvents selected from n-hexanol, n-octanol, 2-octanol, isopentyl ether, and n-hexyl ether. The water-insoluble hydrogen bond acceptor neutral amines are hydrophobic triamines with the molecular formula R1R2N(CH2). n NR(CH2) n CONR3R4, R1, R2, R3, R4 are C3-C 10 One or more of them, where R is H or C1-C 10 In the alkyl hydrocarbon molecular formula, n is one or more of 1, 2, or 3; The volume ratio of water-insoluble hydrogen bond acceptor neutral amines to diluent is (0.1-10):1; A method for separating and purifying aconitic acid includes the following steps: S1. Mix water-insoluble hydrogen bond acceptor neutral amines with diluents at a volume ratio of (0.1-10):1 to obtain an in-situ hydrophobic supramolecular system for separating and purifying aconitic acid. S2. Mix the in-situ hydrophobic supramolecular system obtained in S1 with the fermentation broth containing aconitic acid, so that the aconitic acid associates with the in-situ hydrophobic supramolecular system to obtain a hydrophobic supramolecular system with associated aconitic acid. S3. Wash the hydrophobic supramolecular associated with aconitic acid with detergent to purify and remove impurities from the hydrophobic supramolecular associated with aconitic acid. S4. The purified aconitic hydrophobic supramolecular associating with aconitic acid obtained in step S3 is mixed with the desorbing agent and heated to destroy the internal forces of the aconitic acid and hydrophobic supramolecular system, thereby obtaining the hydrophobic supramolecular and the desorbed high-purity aconitic acid solution; the high-purity aconitic acid solution is then deoiled, decolorized, concentrated and crystallized to obtain the aconitic acid solid product. S5. The hydrophobic supramolecular obtained in step S4 is thoroughly mixed with the purifying agent. The hydrophobic supramolecular reacts fully with the purifying agent to remove residual impurities from the hydrophobic supramolecular. It is then further associated with the aconitic acid fermentation broth to prepare aconitic acid-containing hydrophobic supramolecular.

2. A method for separating and purifying aconitic acid, characterized in that, Includes the following steps: S1. Mix water-insoluble hydrogen bond acceptor neutral amines with diluents at a volume ratio of (0.1-10):1 to obtain an in-situ hydrophobic supramolecular system for separating and purifying aconitic acid. S2. Mix the in-situ hydrophobic supramolecular system obtained in S1 with the fermentation broth containing aconitic acid, so that the aconitic acid associates with the in-situ hydrophobic supramolecular system to obtain a hydrophobic supramolecular system with associated aconitic acid. S3. Wash the hydrophobic supramolecular associated with aconitic acid with detergent to purify and remove impurities from the hydrophobic supramolecular associated with aconitic acid. S4. The purified aconitic hydrophobic supramolecular associating with aconitic acid obtained in step S3 is mixed with the desorbing agent and heated to destroy the internal forces of the aconitic acid and hydrophobic supramolecular system, thereby obtaining the hydrophobic supramolecular and the desorbed high-purity aconitic acid solution; the high-purity aconitic acid solution is then deoiled, decolorized, concentrated and crystallized to obtain the aconitic acid solid product. S5. The hydrophobic supramolecular obtained in step S4 is thoroughly mixed with the purifying agent. The hydrophobic supramolecular reacts fully with the purifying agent to remove residual impurities from the hydrophobic supramolecular. It is then further associated with the aconitic acid fermentation broth to prepare aconitic acid-containing hydrophobic supramolecular.

3. The method for separating and purifying aconitic acid according to claim 2, characterized in that, In step S2, the volume ratio of the in-situ hydrophobic supramolecular molecules to the aconitine fermentation broth is (1-5):

1.

4. The method for separating and purifying aconitic acid according to claim 2, characterized in that, In step S4, the volume ratio of the purified hydrophobic supramolecular aconitine to the eluent is (1-5):

1.

5. The method for separating and purifying aconitic acid according to claim 2, characterized in that, The detergent is one or more of aconitic acid and sodium aconitic acid.

6. The method for separating and purifying aconitic acid according to claim 2, characterized in that, The eluent is sodium hydroxide, sodium aconitate, and water, and the concentration of the eluent is (0-3) mol / L.

7. The method for separating and purifying aconitic acid according to claim 2, characterized in that, The purifying agent is an alkaline solution.