Method for recovering D-chiro-inositol mother liquor

Abstract

The invention discloses a method for recovering D-chiral inositol mother liquor, and relates to the technical field of D-chiral inositol production.The method comprises the steps that ethyl alcohol is added into the D-chiral inositol mother liquor, and then cooling and suction filtration are conducted to obtain filtrate I and a solid I; adding the solid I into purified water, stirring at 50-60 DEG C for 1-2 hours, concentrating, adding ethanol, cooling, and carrying out suction filtration to obtain filtrate II and a solid II; combining the filtrate I and the filtrate II, distilling, collecting a dealcoholization solution and an ethanol recovery solution, carrying out thermal concentration on the obtained dealcoholization solution until the solid content is 45-55% w / w, adding ethanol into the obtained concentrated solution, cooling, and carrying out suction filtration to obtain a filtrate III and a solid III; and adding purified water into the solid III for dissolving, then adding 1-5% v / v of activated carbon for decoloration, then carrying out suction filtration to obtain a decolorized solution, then adding ethanol, cooling, and carrying out suction filtration to obtain a D-chiro-inositol finished product and a filtrate IV, thereby improving the yield and purity of the product.

Description

Technical Field

[0001] This invention relates to the field of D-chiral inositol production technology, and specifically to a method for recovering D-chiral inositol mother liquor. Background Technology

[0002] D-ChiroInositol (DCI), a white powder, is readily soluble in water and slightly soluble in organic solvents such as ethanol and methanol. It is one of the nine isomers of inositol with optical activity and is also the bioactive isomer of vitamin B8. It exists in relatively high levels in buckwheat seeds, soybeans, and some insects, primarily as methylated or glycosylated derivatives, and is a biodegradation product of buckwheat glycosides. It possesses insulin-sensitizing properties and promotes hepatic fat metabolism, significantly lowering blood glucose levels and showing a significant therapeutic effect on diabetes. Furthermore, DCI also has effects such as improving polycystic ovary syndrome (PCOS), anti-oxidation, anti-aging, and free radical scavenging, making it of good practical value.

[0003] D-Chiral inositol can be extracted from plants such as buckwheat; however, the content of D-chiral inositol in these plants is low, resulting in poor resource utilization and high extraction costs. D-chiral inositol can also be prepared through organic synthesis, but this method is cumbersome, byproducts are difficult to separate, and toxic residues may remain, affecting product quality. Furthermore, it requires large amounts of organic solvents, making it environmentally unfriendly. Additionally, D-chiral inositol can be produced by hydrolyzing D-pineol or kasugamycin; however, the raw materials D-pineol or kasugamycin are expensive, making it uneconomical.

[0004] In recent years, with the development of production engineering technology, bioconversion synthesis of D-chiral inositol has become a new development trend. Currently, the main method involves modifying microorganisms to convert muscle inositol into D-chiral inositol, and then obtaining a product with high chemical and optical purity through crystallization. The mother liquor contains approximately 15-25% D-chiral inositol, 5-15% water, 60-80% ethanol, and a small amount of pigment. Currently, the mother liquor is often recycled, but repeated recycling can easily reduce the purity of the product. In addition, the limited amount of mother liquor recycled each time leads to an excess of mother liquor, resulting in significant storage and environmental pressures. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a method for recovering D-chiral inositol mother liquor, which improves the economic benefits of the product and reduces storage and environmental pressure, in order to address the shortcomings of the existing technology.

[0006] To solve the above-mentioned technical problems, the technical solution of the present invention is as follows:

[0007] A method for recovering D-chiral inositol mother liquor includes the following steps:

[0008] A: Ethanol was added to the D-chiral inositol mother liquor, then the temperature was lowered and the mixture was filtered to obtain filtrate I and solid I;

[0009] B: Add solid I to purified water and stir at 50-60℃ for 1-2 hours. Concentrate to a solid content of 30-35% w / w. Add 1-1.5 times the volume of the solution of ethanol, then cool and filter to obtain filtrate II and solid II.

[0010] C: Combine filtrate I and filtrate II, distill them, collect the dealcoholized liquid and ethanol recovery liquid, heat concentrate the obtained dealcoholized liquid to a solid content of 45-55% w / w, add ethanol to the obtained concentrate, cool and filter to obtain filtrate III and solid III.

[0011] D: Solid III is dissolved in purified water, then 1-5% v / v activated carbon is added for decolorization, followed by filtration to obtain the decolorized solution. Ethanol is then added, followed by cooling and filtration to obtain the D-chiral inositol product and filtrate IV.

[0012] Preferably, the D-chiral inositol mother liquor in step A is taken from filtrate II and filtrate III disclosed in Chinese Patent CN 120518441 A.

[0013] Preferably, in step A, the amount of ethanol added is 1.0-1.5 times the volume of the D-chiral inositol mother liquor, and the mixture is cooled to 15-20°C before being filtered.

[0014] The D-chiral inositol content of filtrate I is >80%, while the D-chiral inositol content of solid I is between 5-15%.

[0015] Preferably, in step B, the amount of purified water added is 0.8-1.0 times the weight of solid I, and the mixture is cooled to 25-30°C before being filtered.

[0016] The D-chiral inositol content of filtrate II is >80%, while the D-chiral inositol content of solid II is between 0.5% and 1.5%.

[0017] Preferably, solid II in step B is used for the conversion of the next batch of D-chiral inositol.

[0018] Preferably, the ethanol recovery solution in step C is used for crystallization of the decolorizing solution in the later stage of step D.

[0019] Preferably, in step C, the amount of ethanol added is 0.7-0.9 times the volume of the concentrated liquid, and then the temperature is lowered to 25-30°C before filtration.

[0020] The chiral inositol content of filtrate III is <75%, while the chiral inositol content of solid III is 92-97%.

[0021] Preferably, in step D, the amount of purified water added is 1-1.5 times the weight of solid III, and the dissolution temperature of solid III is 60-80℃.

[0022] Preferably, in step D, ethanol is added dropwise to the decolorizing solution until crystals precipitate, then the solution is cooled to 20-25°C and filtered.

[0023] Preferably, filtrate III and filtrate IV are reused in the first alcohol addition of the next batch of D-chiral inositol mother liquor.

[0024] Due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0025] 1. The entire process of this invention is designed with a purification path of "mother liquor → preliminary enrichment → washing and purification → merging and refining → deep purification → finished product". Each step is designed to remove specific impurities, thereby achieving a stepwise increase in purity.

[0026] 2. Solid I is washed with water by controlling the dissolution temperature, and ethanol is added and the cooling crystallization temperature is controlled to allow as much D-chiral inositol as possible to enter filtrate II, which facilitates the gradient separation of D-chiral inositol in the subsequent mother liquor and improves the product yield.

[0027] 3. Solid I, which might be discarded in traditional processes, is specifically treated with purified water in this invention, recovering 5-15% of D-chiral inositol (which enters filtrate II), significantly reducing the loss of active ingredients. The recycling of filtrates III and IV improves raw material utilization, greatly avoids waste, and is environmentally friendly. Furthermore, the ethanol recovered by distillation in step C is directly used in the crystallization process of step D, achieving closed-loop solvent utilization within the system and reducing production costs.

[0028] 4. This invention constructs a highly efficient and environmentally friendly recycling system by optimizing the combination of unit operations such as stepwise crystallization, washing, decolorization, and recrystallization, and by creatively introducing a multi-material recycling mechanism. This system not only improves the product purity from the mother liquor state to 92-97% or even higher finished product standards through multi-stage purification steps, but more importantly, through comprehensive recycling and reuse, it recovers and utilizes almost all D-chiral inositol contained in all stages, thereby increasing the overall yield to a level that is difficult to achieve with traditional methods, while simultaneously reducing emissions of waste gas, wastewater, and solid waste, making it extremely valuable for industrial applications. Attached Figure Description

[0029] Figure 1 This is a liquid chromatogram of the D-chiral inositol product in Example 1 of the present invention;

[0030] Figure 2 This is a liquid chromatogram of the D-chiral inositol product in Example 2 of the present invention;

[0031] Figure 3 This is a liquid chromatogram of the D-chiral inositol product in Example 3 of the present invention;

[0032] Figure 4 This is a liquid chromatogram of the D-chiral inositol product in Example 4 of the present invention. Detailed Implementation

[0033] The present invention will be further illustrated below with reference to the embodiments. Example 1

[0034] 1. Take 50L of filtrate II and filtrate III disclosed in Chinese Patent CN 120518441 A and combine them (the content of D-chiral inositol is 100g / L). Add 1.0 times (50L) of ethanol, then cool to 15℃ and filter to obtain 80L of filtrate I and 15kg of solid I. The chiral inositol content of filtrate I is 84.5%, and the chiral inositol content of solid I is 8.5%.

[0035] 2. Add 0.8 times (12L) of water to solid I, stir at 50°C for 1 hour, concentrate to 30% w / w solid content, add 1 times the volume of ethanol of the solution, then cool to 25°C, filter, and obtain 23.0L of filtrate II and 13kg of solid II, wherein the chiral inositol content of filtrate II is 83% and the chiral inositol content of solid II is 0.8%.

[0036] 3. Combine filtrates I and II to 103 L, distill, and collect 75 L of ethanol recovery liquid and 15 L of dealcoholized liquid. Concentrate the dealcoholized liquid by heat to a solid content of 45% w / w (7.3 L). Then slowly add 0.7 times 5.0 L of ethanol, slowly cool to 25 °C, and filter to obtain 11 L of filtrate III and 4 kg of solid III. The chiral inositol content of filtrate III is 72.0%, and the chiral inositol content of solid III is 94.5%.

[0037] 4. Solid III was dissolved in 4L of water at 60℃, then 1% v / v activated carbon was added for decolorization, followed by filtration to obtain 6.5L of decolorized solution. Ethanol was then added dropwise until crystals precipitated. The temperature was lowered to 20℃, and filtration was performed to obtain 3.66kg of chiral inositol product, with a yield of 91.5% and a purity of 99.4%. 4.5L of filtrate IV was also obtained. Example 2

[0038] 1. Take 50L of filtrate II and filtrate III disclosed in Chinese Patent CN 120518441 A and combine them (the content of D-chiral inositol is 100g / L). Add 1.2 times (60L) of ethanol, then cool to 17℃ and filter to obtain 100L of filtrate I and 16kg of solid I. The chiral inositol content of filtrate I is 85.5%, and the chiral inositol content of solid I is 6.5%.

[0039] 2. Add 0.9 times (14 L) of water to solid I, stir at 55 °C for 1.5 h, concentrate to a solid content of 32% w / w, add 1.2 times the volume of the solution of ethanol, then cool to 28 °C, filter, and obtain 27.5 L of filtrate II and 14.5 kg of solid II, wherein the chiral inositol content of filtrate II is 84.0% and the chiral inositol content of solid II is 0.60%.

[0040] 3. Combine filtrates I and II to form 127.5 L, distill, and collect 100 L of ethanol recovery liquid and 24 L of dealcoholized liquid. Concentrate the dealcoholized liquid by heat to a solid content of 48% w / w (10 L). Then slowly add 0.8 times the volume of 8 L of ethanol, slowly cool to 27 °C, and filter to obtain 15 L of filtrate III and 4.2 kg of solid III. The chiral inositol content of filtrate III is 70.5%, and the chiral inositol content of solid III is 95.5%.

[0041] 4. Solid III was dissolved in 1.2 times 5L of water at 65℃, then 2% v / v activated carbon was added for decolorization, followed by filtration to obtain 8.0L of decolorized solution. Ethanol was then added dropwise until crystals precipitated. The temperature was lowered to 23℃, and filtration was performed to obtain 3.9kg of chiral inositol product with a yield of 92.5% and a purity of 99.5%. 6.5L of filtrate IV was also obtained. Example 3

[0042] 1. Take 50L of filtrate II and filtrate III disclosed in Chinese Patent CN 120518441 A and combine them (the content of D-chiral inositol is 100g / L). Add 1.5 times (75L) of ethanol, then cool to 20℃ and filter to obtain 110L of filtrate I and 17kg of solid I. The chiral inositol content of filtrate I is 86.5%, and the chiral inositol content of solid I is 5.0%.

[0043] 2. Add 1.0 times (17L) of water to solid I, stir at 60°C for 2 hours, concentrate to a solid content of 34% w / w, add 1.4 times the volume of the solution of ethanol, then cool to 30°C, filter, and obtain 45.0L of filtrate II and 15kg of solid II, wherein the chiral inositol content of filtrate II is 85.5% and the chiral inositol content of solid II is 0.6%.

[0044] 3. Combine filtrates I and II to 155 L, distill, and collect 120 L of ethanol recovery liquid and 28 L of dealcoholized liquid. Concentrate the dealcoholized liquid by heat to a solid content of 55% w / w (10 L). Then slowly add 0.9 times 9 L of ethanol, slowly cool to 30 °C, and filter to obtain 17.5 L of filtrate III and 4.4 kg of solid III. The chiral inositol content of filtrate III is 69.5%, and the chiral inositol content of solid III is 96%.

[0045] 4. Solid III was dissolved in 6.6 L of water at 80 °C, then 5% v / v activated carbon was added for decolorization. The solution was then filtered to obtain 9 L of decolorized solution. Ethanol was then added dropwise until crystals precipitated. The solution was cooled to 25 °C and filtered to obtain 4.1 kg of chiral inositol product with a yield of 93% and a purity of 99.6%. 7.5 L of filtrate IV was also obtained. Example 4

[0046] 1. Take 50L of filtrate II and filtrate III disclosed in Chinese Patent CN 120518441 A (the content of D-chiral inositol is 100g / L), add 1.4 times (70L) of ethanol and filtrate III and IV from Example 3, then cool to 15°C and filter to obtain 130L of filtrate I and 25kg of solid I, wherein the chiral inositol content of filtrate I is 87.0% and the chiral inositol content of solid I is 7.0%.

[0047] 2. Add 1.0 times (25L) of water to solid I, stir at 60°C for 2 hours, concentrate to a solid content of 35% w / w, add 1.5 times the volume of ethanol of the solution, then cool to 25°C, filter, and obtain 50L of filtrate II and 20kg of solid II, wherein the chiral inositol content of filtrate II is 85.5% and the chiral inositol content of solid II is 0.55%.

[0048] 3. Combine filtrates I and II to 180L, distill, and collect 145L of ethanol recovery liquid and 30L of dealcoholized liquid. Heat-concentrate the dealcoholized liquid to a solid content of 55% w / w (12L). Then slowly add 0.9 times the amount of ethanol (10.8L), slowly cool to 25°C, and filter to obtain 19.0L of filtrate III and 4.9kg of solid III. The chiral inositol content of filtrate III is 70.5%, and the chiral inositol content of solid III is 96.0%.

[0049] 4. Solid III was dissolved in 7.3 L of water (1.5 times the volume) at 80 °C. Then, 5% v / v activated carbon was added for decolorization. The solution was then filtered to obtain 10 L of decolorized solution. The ethanol recovery solution from Example 3 was added dropwise first, followed by normal ethanol, until crystals precipitated. The solution was then cooled to 20 °C and filtered to obtain 4.6 kg of chiral inositol product, with a yield of 94% and a purity of 99.6%. 8.5 L of filtrate IV was also obtained.

[0050] It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be understood that after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims.

Claims

1. A method for the recovery of a D-chiro-inositol mother liquor, characterized in that The process comprises the following steps: A: adding ethanol to the D-chiro-inositol mother liquor, then cooling and filtering to obtain filtrate I and solid I; B: adding purified water to solid I, stirring at 50-60℃ for 1-2h, concentrating to a solid content of 30-35% w / w, adding 1-1.5 times the volume of ethanol as the dissolving liquid, then cooling and filtering to obtain filtrate II and solid II; C: combining filtrate I and filtrate II, distilling to obtain dealcoholized liquid and ethanol recovery liquid, then hot-concentrating the dealcoholized liquid to a solid content of 45-55% w / w, adding ethanol to the concentrated liquid, cooling and filtering to obtain filtrate III and solid III; D: adding purified water to solid III to dissolve, then adding 1-5% v / v activated carbon to decolorize, then filtering to obtain a decolorized liquid, then adding ethanol, cooling and filtering to obtain D-chiro-inositol product and filtrate IV.

2. A process for the recovery of D-chiro-inositol mother liquor according to claim 1, characterized by the fact that: The amount of ethanol added in step A is 1.0-1.5 times the volume of the D-chiro-inositol mother liquor, and the filtering is performed after cooling to 15-20℃; The D-chiro-inositol content of filtrate I is >80%, and the D-chiro-inositol content of solid I is between 5-15%.

3. A method of recovering a D-chiro-inositol mother liquor according to claim 1, characterized by: The amount of purified water added in step B is 0.8-1.0 times the weight of solid I, and the filtering is performed after cooling to 25-30℃; The D-chiro-inositol content of filtrate II is >80%, and the D-chiro-inositol content of solid II is between 0.5-1.5%.

4. A method of recovering a D-chiro-inositol mother liquor according to claim 1, characterized by: Solid II in step B is used for the conversion of the next batch of D-chiro-inositol.

5. A method of recovering a D-chiro-inositol mother liquor according to claim 1, characterized by: The ethanol recovery liquid in step C is used for the crystallization of the decolorized liquid in step D.

6. A method of recovering a D-chiro-inositol mother liquor according to claim 1, characterized by: The amount of ethanol added in step C is 0.7-0.9 times the volume of the concentrated liquid, and the filtering is performed after cooling to 25-30℃; The D-chiro-inositol content of filtrate III is <75%, and the D-chiro-inositol content of solid III is between 92-97%.

7. A method of recovering a D-chiro-inositol mother liquor according to claim 1, characterized by: The amount of purified water added in step D is 1-1.5 times the weight of solid III, and the dissolution temperature of solid III is 60-80℃.

8. The method of recovering a D-chiro-inositol mother liquor of claim 1, wherein: In step D, ethanol is added dropwise to the decolorized liquid until crystals begin to precipitate, then the filtering is performed after cooling to 20-25℃.

9. A method of recovering a D-chiro-inositol mother liquor according to claim 1, characterized by: Filtrate III and filtrate IV are used for the first ethanol addition in the next batch of D-chiro-inositol mother liquor.

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