A method for recycling mother liquor in the preparation of scyllo-inositol

Abstract

The invention discloses a method for recycling a mother liquor in the preparation of scyllo-inositol, and relates to the technical field of scyllo-inositol production. The method comprises the following steps: taking a scyllo-inositol crystallization mother liquor, collecting a distillate and a residual distillate after distillation, wherein the distillate is applied to scyllo-inositol crystallization; adding 1-3% w / v activated carbon to the residual distillate for decolorization, filtering and collecting the decolorized liquid; concentrating the decolorized liquid at a temperature of 60-80° C. and a vacuum of less than 0.09 MPa to obtain a concentrated liquid; and cooling the concentrated liquid to 10-15° C. at a stirring speed of 50-100 rpm, filtering to obtain boric acid crystals and a filtrate. The method greatly reduces production costs, reduces waste of raw materials, and is environmentally friendly.

Description

Technical Field

[0001] The invention relates to the technical field of scyllo-inositol production, and in particular to a method for recycling mother liquor in the preparation of scyllo-inositol. Background Art

[0002] Scyllo-inositol (SI), a diastereomer of myo-inositol (MI), is found in plants, animals, and some bacteria, but its natural content is far lower than that of myo-inositol. Studies have shown that scyllo-inositol is effective in treating brain disorders such as Alzheimer's disease, Down syndrome, and Angelman syndrome. Furthermore, scyllo-inositol can lower uric acid levels and is used to treat hyperuricemia.

[0003] In recent years, with the development of bioengineering technology, the biological preparation of scyllo-inositol has become a new development trend. Boric acid and crude enzyme solution are added to myo-inositol for conversion. Myo-inositol is converted into scyllo-inositol and then into scyllo-inositol. By pre-adding boric acid to react with the generated scyllo-inositol, a borate scyllo-inositol complex salt precipitate is obtained, thereby achieving the purpose of scyllo-inositol separation. Phosphoric acid is then used to decompose the complex salt, and then ethanol is added to obtain scyllo-inositol. This method will produce a large amount of mother liquor while obtaining scyllo-inositol. The mother liquor contains ethanol, phosphoric acid, boric acid, water and a small amount of metal ions. Reasonable recycling and utilization of various components in the mother liquor can not only reduce production costs, but also achieve the purpose of energy conservation and emission reduction. Summary of the Invention

[0004] The technical problem to be solved by the present invention is: in view of the shortcomings of the existing technology, a method for recycling the mother liquor in the preparation of scyllo-inositol is provided. By recycling the mother liquor in the preparation of scyllo-inositol, the cost is greatly reduced, the waste of raw materials is reduced, less hazardous waste is generated in the process, and it is environmentally friendly.

[0005] In order to solve the above technical problems, the technical solution of the present invention is:

[0006] A method for recycling mother liquor in the preparation of scyllo-inositol comprises the following steps:

[0007] A: Take the mother liquor of scyllo-inositol crystallization, distill it, collect the distillate and the residual liquid, and use the distillate to make scyllo-inositol crystallization;

[0008] B: Add 1-3% w / v activated carbon to the distillation residue for decolorization, and collect the decolorized liquid after filtration;

[0009] C: The decolorized solution is concentrated at a temperature of 60-80°C and a vacuum of less than -0.09 MPa to obtain a concentrated solution;

[0010] D: The concentrated solution is cooled to 10-15°C while stirring at 50-100 rpm, and filtered to obtain boric acid crystals and filtrate.

[0011] Preferably, the scyllo-inositol crystallization mother liquor in step A contains 38-42% wt of ethanol, 4-6% wt of phosphoric acid, 4-6% wt of boric acid, 0.05-0.5% wt of scyllo-inositol, and the remainder is water.

[0012] Preferably, the distillation conditions in step A are a temperature of 60 to 70° C. and a vacuum pressure of -0.085 to -0.09 MPa.

[0013] Preferably, the decolorization condition in step B is decolorization at 40-50° C. for 20-40 min.

[0014] Preferably, the solid content of the concentrated solution in step C is 30-40% w / w.

[0015] Preferably, the cooling rate of the concentrated solution in step D is 3-5°C / h.

[0016] Preferably, the boric acid crystals in step D are washed with cold water at 2-4° C. to a purity of >98% and then used to form a complex salt with scyllo-inositol.

[0017] Preferably, the filtrate in step D is diluted with water to 5-10% wt and used for acid hydrolysis of scyllo-inositol borate complex salt.

[0018] Due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0019] 1. All ethanol, phosphoric acid and boric acid contained in the mother liquor except water can be recovered, which greatly reduces production costs and reduces the waste of raw materials.

[0020] 2. The recovered ethanol has a concentration of ≥93%, a boric acid purity of ≥98.8%, and a phosphoric acid concentration of 5-10% wt, and can be directly used in the production of scyllo-inositol. Continuous recycling and recovery greatly reduces the cost of raw materials.

[0021] 3. By recovering ethanol, phosphoric acid and boric acid in the mother liquor, no hazardous waste will be generated during the recovery process, which is environmentally friendly. DETAILED DESCRIPTION

[0022] The present invention will be further described below with reference to the embodiments.

[0023] Example 1

[0024] A method for recycling mother liquor in the preparation of scyllo-inositol, characterized by comprising the following steps:

[0025] A: Take 2L of scyllo-inositol crystallization mother liquor (40%wt ethanol, 5%wt phosphoric acid, 5%wt boric acid, 0.05%wt scyllo-inositol, and the rest water) and distill it at 60°C and vacuum pressure of -0.09MPa. Collect 0.95L of distillate and 1.1L of raffinate. The distillate is an ethanol solution with a concentration of 93%, and apply it to the crystallization step in the preparation of scyllo-inositol.

[0026] B: Add 1% w / v activated carbon to the distilled solution and decolorize at 40°C for 40 min. Filter and collect 1.1 L of the decolorized solution.

[0027] C: The decolorized solution is concentrated at 60°C and vacuum <-0.09 MPa to obtain a concentrated solution with a solid content of 30% w / w;

[0028] D: The concentrate was cooled to 15°C at a rate of 3°C / h with stirring at 50 rpm. Filtering was performed to obtain 94 g of wet boric acid crystals and 0.25 L of filtrate. The boric acid crystals were washed with 4°C cold water and then dried. The weight of the boric acid crystals was 85 g with a purity of 98.8%. These crystals were used in the preparation of scyllo-inositol to form a complex salt precipitation with scyllo-inositol.

[0029] E: The filtrate is a phosphoric acid solution with a weight of 310 g and a concentration of 40% wt. It is diluted to 5-10% wt by adding water and used in the acidolysis step of scyllo-inositol borate complex salt in the preparation of scyllo-inositol.

[0030] Example 2

[0031] A method for recycling mother liquor in the preparation of scyllo-inositol, characterized by comprising the following steps:

[0032] A: Take 2L of scyllo-inositol crystallization mother liquor (40%wt ethanol, 5%wt phosphoric acid, 5%wt boric acid, 0.05%wt scyllo-inositol, and the rest water) and distill it at 65°C and vacuum pressure of -0.085MPa. Collect 0.94L of distillate and 1.11L of raffinate, wherein the distillate is an ethanol solution with a concentration of 94%, and apply it to the crystallization step in the preparation of scyllo-inositol.

[0033] B: Add 2% w / v activated carbon to the distilled solution and decolorize at 45°C for 30 min. Filter and collect 1.11 L of the decolorized solution.

[0034] C: The decolorized solution was concentrated at 70°C under vacuum <-0.09 MPa to obtain a concentrated solution with a solid content of 35% w / w;

[0035] D: The concentrate was cooled to 12°C at a rate of 4°C / h with stirring at 80 rpm. Filtering yielded 101 g of boric acid crystals and 0.22 L of filtrate. The boric acid crystals were washed with 4°C cold water and dried, weighing 91 g with a purity of 99.2%. These crystals were used in the preparation of scyllo-inositol to form a complex salt precipitation with scyllo-inositol.

[0036] E: The filtrate is a phosphoric acid solution, weighing 275 g and having a concentration of 45% wt. It is diluted to 5-10% wt by adding water and used in the acidolysis step of scyllo-inositol borate complex salt in the preparation of scyllo-inositol.

[0037] Example 3

[0038] A method for recycling mother liquor in the preparation of scyllo-inositol, characterized by comprising the following steps:

[0039] A: Take 2L of scyllo-inositol crystallization mother liquor (40%wt ethanol, 5%wt phosphoric acid, 5%wt boric acid, 0.05%wt scyllo-inositol, and the rest water) and distill it at 70°C and vacuum pressure of -0.09MPa. Collect 0.92L of distillate and 1.13L of raffinate, wherein the distillate is an ethanol solution with a concentration of 95%, and apply it to the crystallization step in the preparation of scyllo-inositol.

[0040] B: Add 3% w / v activated carbon to the distillation residue and decolorize at 50°C for 20 min. Filter and collect 1.13 L of the decolorized liquid.

[0041] C: The decolorized solution is concentrated at 80°C and vacuum <-0.09 MPa to obtain a concentrated solution with a solid content of 40% w / w;

[0042] D: The concentrate was cooled to 10°C at a rate of 5°C / h with stirring at 100 rpm. Filtering yielded 110 g of boric acid crystals and 0.2 L of filtrate. The boric acid crystals were washed with 4°C cold water and dried, weighing 97 g with a purity of 99.1%. These crystals were used in the preparation of scyllo-inositol to form a complex salt precipitation with scyllo-inositol.

[0043] E: The filtrate is a phosphoric acid solution, weighing 252 g and having a concentration of 50% wt. It is diluted to 5-10% wt by adding water and used in the acidolysis step of scyllo-inositol borate complex salt in the preparation of scyllo-inositol.

[0044] It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the scope limited by the appended claims of the application.

Claims

1. A method for recycling mother liquor in the preparation of scyllo-inositol, characterized in that The following steps are involved: A: Take the mother liquor of scyllo-inositol crystallization, collect the distillate and the residual liquid after distillation, wherein the distillate is applied to the crystallization of scyllo-inositol, wherein the mother liquor of scyllo-inositol crystallization contains 38-42%wt of ethanol, 4-6%wt of phosphoric acid, 4-6%wt of boric acid, 0.05-0.5%wt of scyllo-inositol, and the rest is water; B: Add 1-3% w / v activated carbon to the distillation residue for decolorization, and collect the decolorized liquid after filtration; C: The decolorized solution is concentrated at a temperature of 60-80°C and a vacuum of less than -0.09 MPa to obtain a concentrated solution; D: The concentrated solution is cooled to 10-15°C while stirring at 50-100 rpm, and filtered to obtain boric acid crystals and filtrate.

2. The method for recycling mother liquor in the preparation of scyllo-inositol according to claim 1, wherein: The distillation conditions of step A are a temperature of 60 to 70° C. and a vacuum pressure of -0.085 to -0.09 MPa.

3. The method for recycling mother liquor in the preparation of scyllo-inositol according to claim 1, wherein: The decolorization condition in step B is decolorization at 40-50° C. for 20-40 minutes.

4. The method for recycling mother liquor in the preparation of scyllo-inositol according to claim 1, wherein: The solid content of the concentrate in step C is 30-40% w / w.

5. The method for recycling mother liquor in the preparation of scyllo-inositol according to claim 1, wherein: The cooling rate of the concentrated solution in step D is 3-5°C / h.

6. The method for recycling mother liquor in the preparation of scyllo-inositol according to claim 1, wherein: In step D, the boric acid crystals are washed with cold water at 2-4° C. to a purity of >98%, and then used to form a complex salt with scyllo-inositol.

7. The method for recycling mother liquor in the preparation of scyllo-inositol according to claim 1, wherein: The filtrate in step D is a phosphoric acid solution, which is diluted to 5-10% wt by adding water and used for acid hydrolysis of scyllo-inositol borate complex salt.