Environment-friendly production process of L-cystine

Abstract

The invention discloses an environment-friendly production process of L-cystine, and relates to the technical field of L-cystine production processes, and the process comprises the following steps: pouring a fermentation broth into a filter, carrying out preliminary centrifugal filtration to filter out large impurities, then pouring the filtered liquid into a tubular ultrafiltration membrane, carrying out secondary filtration to filter out small impurities, and carrying out vacuum drying to obtain the L-cystine. And filtering to obtain concentrated bacterial slurry and fermentation clear liquid. By means of the protein decomposition method, waste liquid can be conveniently reutilized to extract L-cystine, resource waste can be reduced, energy conservation and environmental protection are achieved, by means of the ammonia water manufacturing process, resource waste can be reduced, environmental pollution caused by emission of amino acid of waste gas can be prevented, energy conservation and environmental protection are achieved, and the method is suitable for industrial production. Through the set filtering process, multiple times of filtering are beneficial to preventing excessive and overlarge impurities in the fermentation liquor from blocking the infusion tube and affecting the filtering effect in the preparation process.

Description

Technical Field

[0001] The invention relates to the technical field of L-cystine production technology, in particular to an environmentally friendly production technology of L-cystine. Background Art

[0002] Cystine is a natural, non-essential amino acid, chemically known as "alanine." It is a colorless, odorless crystalline solid with high solubility in water. As an important amino acid, cystine has multiple functions and effects. It not only plays an important physiological function in the human body, but also has broad application potential in the fields of medicine, health care, and beauty.

[0003] In the existing cystine production process, the fermentation liquid produced is mostly roughly filtered during the production process. Excessive impurities still remain in the filtered fermentation liquid. During the process of heating and concentrating the fermentation liquid, the impurities in the fermentation liquid can easily cause blockage of the infusion tube on the equipment, affecting the production efficiency. Moreover, the impurities after filtering usually contain a small amount of production raw materials. Directly discarding them will cause waste and is not conducive to environmental protection. Summary of the Invention

[0004] The present invention aims to solve the problem that in the existing cystine production process, the fermentation liquid produced during the production is generally roughly filtered, and excessive impurities still remain in the filtered fermentation liquid. During the process of heating and concentrating the fermentation liquid, the impurities in the fermentation liquid can easily clog the infusion tube on the equipment, affecting the production efficiency. Moreover, the filtered impurities generally contain a small amount of production raw materials, and directly discarding them will cause waste and be detrimental to the environment. The present invention provides an environmentally friendly production process for L-cystine.

[0005] To achieve the above object, the present invention provides the following technical solution: an environmentally friendly production process for L-cystine, comprising the following steps:

[0006] S1, the fermentation liquid is poured into the filter for preliminary centrifugal filtration to filter out large impurities, and then the filtered liquid is poured into the tubular ultrafiltration membrane for secondary filtration to filter out small impurities, and after filtration, a concentrated bacterial slurry and fermentation clear liquid are obtained;

[0007] S2. Pour the concentrated bacterial slurry into a blender and add a certain amount of water, stirring at a speed of 100-1000 rpm for 20-30 minutes, heating to 30 degrees, adding the extract, extracting the amino acids in the concentrated bacterial slurry, adding an oxidant to the amino acids to obtain ammonia, and injecting the ammonia into water to obtain ammonia water for later use;

[0008] S3, placing the resin in the fermentation clear liquid for soaking for 10-30 hours, so that L-cystine is exchanged on the resin, pouring the soaked solution into a filter, filtering it and then discharging it into a collection container, extracting the protein in the liquid, and separating it by hydrolysis to obtain L-cystine;

[0009] S4. Place the exchanged resin in 5% to 10% ammonia water and soak for 30 to 60 minutes to elute the L-cystine on the resin. Collect the eluted ammonia water for later use.

[0010] S5. The collected ammonia eluate is decompressed and deaminated by a vacuum pump. The deaminated liquid is poured into activated carbon, which decolorizes the liquid. The decolorized liquid is poured into a concentration device for concentration and crystallization. The concentrated crystals are separated and dried to obtain L-cystine with high purity.

[0011] As a further solution of the present invention: the resin in S3 is treated by repeatedly soaking and washing the resin with deionized water for 5-10 times, then soaking it in a saturated NaCl solution for 30-40 hours, and then soaking it in a 3mol / L-4mol / L'HCl solution and a 3mol / L-4mol / L'NaOH solution for 5-10 times, each time for about 5-10 hours, and then washing it with distilled water until neutral for use.

[0012] As a further solution of the present invention: when the deionized water is used to soak the resin, the deionized water needs to be heated to 30 degrees and 40 degrees.

[0013] As a further embodiment of the present invention: a step of producing L-cystine from the protein in S3;

[0014] A1. Proteins are hydrolyzed under the action of acids, alkalis or enzymes, breaking them down into smaller polypeptides and eventually into amino acids.

[0015] A2. L-cystine is extracted from the various amino acids and other small molecules contained in the hydrolyzed mixture through separation and purification technology to obtain Solution B;

[0016] A3. Adjust the pH value of solution B, then pour the pH-adjusted solution B into a concentration device and heat it for concentration and crystallization, separate the concentrated crystals, and dry the separated crystals.

[0017] As a further solution of the present invention: in the process of producing the fermentation broth, the strain is inoculated into a fermentation tank, the strain is activated using a culture medium containing glucose, the temperature is controlled at 40-45 degrees, the dissolved oxygen in the fermentation tank is maintained at 45%-60%, the stirring speed is 50 rpm-100 rpm, and when the glucose is exhausted, the fermentation is completed to obtain the fermentation broth.

[0018] As a further solution of the present invention: the separation and purification in A2 are respectively: filtration precipitation, ion exchange chromatography and solvent extraction.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] 1. The protein decomposition method is set up to facilitate the secondary utilization of waste liquid to extract L-cystine, which is beneficial to reduce resource waste and is more energy-saving and environmentally friendly. The ammonia production process is set up to reduce resource waste and is beneficial to prevent environmental pollution caused by the emission of amino acids in waste gas, which is more energy-saving and environmentally friendly.

[0021] 2. Through the set filtration process, multiple filtrations are helpful to prevent the fermentation liquid from having too many and too large impurities in it during the preparation process, which will clog the infusion tube and affect the filtration effect. DETAILED DESCRIPTION

[0022] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0023] In the embodiment of the present invention, an environmentally friendly production process of L-cystine is provided. The production steps of L-cystine are as follows: Example 1

[0024] S1. 100 strains of the bacterial strain were inoculated into a fermentation tank, and the strains were activated using a medium containing 10 parts of glucose. Water was added, and the mixture was stirred at 50 rpm for 20 minutes. The mixture was then heated to control the temperature at 40°C and maintain the dissolved oxygen in the fermentation tank at 45%. When the glucose was exhausted, fermentation was completed to obtain a fermentation broth.

[0025] S2, pouring the fermentation liquid into a tubular ultrafiltration membrane and controlling the pressure to 1 MPa for filtration, after filtration, obtaining a concentrated bacterial slurry and a fermentation clear liquid, and directly discharging the concentrated bacterial slurry;

[0026] S4, the resin was repeatedly soaked and washed 5 times by 30 degree deionized water, then soaked in saturated NaCl solution for 30h, and then soaked 5 times with 3mol / L HCl solution and 3mol / L NaOH solution, each for about 5h, and then washed with distilled water until neutral for standby use;

[0027] S5, placing the resin in the fermentation supernatant for soaking for 10 hours, so that the L-cystine in the fermentation supernatant is exchanged onto the resin, then pouring the soaked solution into a filter to filter the solution to separate the resin, and discharging the filtered solution;

[0028] S6. Place the exchanged resin in 5% ammonia water and soak for 30 minutes to elute L-cystine from the resin. Collect the eluted ammonia water for later use.

[0029] S7. The collected ammonia eluate is decompressed and deaminated by a vacuum pump. The deaminated liquid is poured into activated carbon, which decolorizes the liquid. The decolorized liquid is poured into a concentration device for concentration and crystallization. The concentrated crystals are separated and dried to obtain L-cystine with high purity.

[0030] Example 2

[0031] S1. 200 strains of the bacterial strain were inoculated into a fermentation tank, and the strains were activated using a medium containing 10 parts of glucose. Water was added, and the mixture was stirred at 100 rpm for 30 minutes. The mixture was then heated to control the temperature at 45°C and maintain the dissolved oxygen in the fermentation tank at 60%. When the glucose was exhausted, fermentation was completed to obtain a fermentation broth.

[0032] S2, the fermentation liquid is poured into the filter for preliminary centrifugal filtration, the centrifugal speed is 300 rpm to separate and filter out large impurities in the solution, and then the filtered liquid is poured into the tubular ultrafiltration membrane to control the pressure to 2 MPa for secondary filtration to filter out small impurities, and after filtration, a concentrated bacterial slurry and fermentation clear liquid are obtained;

[0033] S3. Pour the concentrated bacterial slurry into a blender, add 2 L of water, and stir at a speed of 1000 rpm for 30 minutes. Then, heat the liquid temperature to 30 degrees Celsius, add the extract to extract the amino acids in the concentrated bacterial slurry, add an oxidant to the amino acids, and the amino acids react with the oxidant to produce ammonia and nitrogen. The exhaust gas will not cause air pollution. The ammonia is injected into the water to form ammonia water.

[0034] S4, the resin was repeatedly soaked and washed 10 times by 40 degree deionized water, then soaked in saturated NaCl solution for 40h, and then soaked in 4mol / L HCl solution and 4mol / L NaOH solution for 10 times, each for about 10h, and then washed with distilled water until neutral for standby use;

[0035] S5, resin is placed in the fermentation clear liquid and soaked, soaking time is 30 hours, so that the L-cystine in the fermentation clear liquid is exchanged on the resin, then the solution after soaking is poured into the filter and the solution is filtered, thereby the resin is separated, the filtered solution is discharged into a collection container, the protein in the liquid is extracted, protein is hydrolyzed under the action of acid, alkali or enzyme, so that the protein is decomposed into smaller polypeptides, finally decomposed into amino acids, solvent extraction is utilized, the L-cystine in the multiple amino acids and other small molecules contained in the hydrolyzed mixture is extracted, and B solution is obtained, pH value is adjusted to B solution, then the B solution with adjusted pH value is poured into a concentration device and heated for concentrated crystallization, the concentrated crystals are separated, and the separated crystals are dried;

[0036] S6. Place the exchanged resin in 10% ammonia water and soak for 60 minutes to elute L-cystine from the resin. Collect the eluted ammonia water for later use.

[0037] S7. The collected ammonia eluate is decompressed and deaminated by a vacuum pump. The deaminated liquid is poured into activated carbon, which decolorizes the liquid. The decolorized liquid is poured into a concentration device for concentration and crystallization. The concentrated crystals are separated and dried to obtain L-cystine with high purity.

[0038] According to the above embodiments, it can be concluded that the manufacturing process of embodiment 2 is more energy-saving and environmentally friendly than that of embodiment 1, and equipment blockage is less likely to occur during the manufacturing process, which is conducive to improving the efficiency of the manufacturing process.

[0039] The above is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with this technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solutions and inventive concepts of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. An environmentally friendly production process for L-cystine, comprising the following steps: S1, pouring the fermentation liquid into the filter for preliminary centrifugal filtration to filter out large impurities, and then pouring the filtered liquid into the tubular ultrafiltration membrane for secondary filtration to filter out small impurities, and obtaining concentrated bacterial slurry and fermentation clear liquid after filtration; S2, pour the concentrated bacterial slurry into a stirrer and add a certain amount of water for stirring at a speed of 100 rpm-1000 rpm for 20 minutes-30 minutes, heat to 30 degrees, add extracts, extract the amino acids in the concentrated bacterial slurry, add oxidants to the amino acids to obtain ammonia, and inject the ammonia into water to obtain ammonia water for standby use; S3, placing the resin in the fermentation clear liquid for soaking for 10-30 hours, so that L-cystine is exchanged on the resin, the soaked solution is poured into a filter, filtered and discharged into a collection container, the protein in the liquid is extracted, and L-cystine is obtained by hydrolysis separation; S4, putting the exchanged resin into 5% to 10% ammonia water, soaking for 30 to 60 minutes to elute the L-cystine on the resin, and collecting the eluted ammonia water for later use; S5. The collected ammonia eluate is decompressed and deaminated by a vacuum pump, the deaminated liquid is poured into activated carbon, the activated carbon decolorizes the liquid, the decolorized liquid is poured into a concentration device for concentration and crystallization, the concentrated crystals are separated and dried to obtain L-cystine with higher purity.

2. An environmentally friendly production process for L-cystine according to claim 1, characterized in that: The resin in S3 is treated by repeatedly soaking and washing the resin with deionized water for 5-10 times, then soaking it in a saturated NaCl solution for 30-40 hours, and then soaking it in a 3mol / L-4mol / L'HCl solution and a 3mol / L-4mol / L'NaOH solution for 5-10 times, each time for about 5-10 hours, and then washing it with distilled water until it is neutral for use.

3. An environmentally friendly production process for L-cystine according to claim 2, characterized in that: When the deionized water is used to soak the resin, the deionized water needs to be heated to 30 degrees and 40 degrees.

4. An environmentally friendly production process for L-cystine according to claim 1, characterized in that: The step of producing L-cystine from the protein in S3; A1. Proteins are hydrolyzed under the action of acid, alkali or enzymes, breaking down proteins into smaller polypeptides and eventually into amino acids. A2. L-cystine is extracted from various amino acids and other small molecules contained in the hydrolyzed mixture by separation and purification technology to obtain solution B; A3. Adjust the pH value of solution B, then pour the solution B with adjusted pH value into the concentration equipment for heating to concentrate and crystallize, separate the concentrated crystals, and dry the separated crystals.

5. An environmentally friendly production process for L-cystine according to claim 1, characterized in that: In the production process of the fermentation liquid, the strain is inoculated into a fermentation tank, a culture medium containing glucose is used to activate the strain, the temperature is controlled at 40 degrees to 45 degrees, the dissolved oxygen in the fermentation tank is maintained at 45% to 60%, the stirring speed is 50 rpm to 100 rpm, and when the glucose is exhausted, the fermentation is completed to obtain the fermentation liquid.

6. An environmentally friendly production process for L-cystine according to claim 4, characterized in that: The separation and purification in A2 are: filtration precipitation, ion exchange chromatography and solvent extraction.