CN114394948A - Recycling method of panthenol mother liquor - Google Patents
Recycling method of panthenol mother liquor Download PDFInfo
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- CN114394948A CN114394948A CN202111647239.4A CN202111647239A CN114394948A CN 114394948 A CN114394948 A CN 114394948A CN 202111647239 A CN202111647239 A CN 202111647239A CN 114394948 A CN114394948 A CN 114394948A
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D307/00—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom
- C07D307/02—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom not condensed with other rings
- C07D307/26—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom not condensed with other rings having one double bond between ring members or between a ring member and a non-ring member
- C07D307/30—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom not condensed with other rings having one double bond between ring members or between a ring member and a non-ring member with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to ring carbon atoms
- C07D307/32—Oxygen atoms
- C07D307/33—Oxygen atoms in position 2, the oxygen atom being in its keto or unsubstituted enol form
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C213/00—Preparation of compounds containing amino and hydroxy, amino and etherified hydroxy or amino and esterified hydroxy groups bound to the same carbon skeleton
- C07C213/02—Preparation of compounds containing amino and hydroxy, amino and etherified hydroxy or amino and esterified hydroxy groups bound to the same carbon skeleton by reactions involving the formation of amino groups from compounds containing hydroxy groups or etherified or esterified hydroxy groups
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C213/00—Preparation of compounds containing amino and hydroxy, amino and etherified hydroxy or amino and esterified hydroxy groups bound to the same carbon skeleton
- C07C213/10—Separation; Purification; Stabilisation; Use of additives
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Abstract
The invention provides a method for recycling panthenol mother liquor, which comprises the following steps: evaporating the solvent in the panthenol mother liquor to dryness, adding water to redissolve solute components, adjusting pH to be alkaline by using calcium hydroxide, carrying out heat preservation reaction at the temperature of 80-85 ℃, cooling and precipitating after the reaction is finished, and separating to obtain a calcium pantoate filter cake and a filtrate containing 3-aminopropanol; mixing the calcium pantoate filter cake with sulfuric acid, carrying out heat preservation reaction at the temperature of 80-85 ℃, adding an alkaline calcium-containing compound into a reaction solution after the reaction is finished to precipitate calcium ions, and separating to obtain a calcium sulfate filter cake and a filtrate containing pantoic acid lactone. The method provided by the invention can recover pantolactone and 3-aminopropanol in the panthenol mother liquor with higher yield, is simple to operate and low in cost, and is suitable for industrial application.
Description
Technical Field
The invention belongs to the technical field of chemical industry, and particularly relates to a method for recycling panthenol mother liquor.
Background
Panthenol includes three forms, mixed isomer (DL-form), dextroisomer (D-form) and levoisomer (L-form), in which only the dextroisomer has biological activity and the levoisomer has no biological activity. DL-panthenol is the precursor of vitamin B5, is a white powdery solid, has slight special odor, and is easy to absorb moisture. DL-panthenol is readily soluble in water, ethanol, methanol and propylene glycol, soluble in chloroform and ether, slightly soluble in glycerol, and insoluble in vegetable oils, mineral oils and fats.
DL-panthenol is the equivalent of pantothenic acid and is the precursor of coenzyme A, and can be converted into pantothenic acid to synthesize coenzyme A, promote metabolism of protein, fat and saccharide, protect mucosa and luster on skin surface, and prevent diseases. Panthenol can also be used as nutritional supplement and widely applied in medicine, food and cosmetic industries.
At present, the method for industrially producing DL-panthenol generally comprises the steps of firstly synthesizing panthenol in a solution, and then cooling and crystallizing to separate out panthenol crystals. However, the crystallization method cannot completely separate out the panthenol, a part of panthenol and a small amount of unreacted raw and auxiliary materials remain in the mother liquor, and if the mother liquor is discarded, not only is the resource waste caused, but also the environment is polluted. Therefore, it is necessary to recycle the components in the mother liquor.
Disclosure of Invention
Aiming at the defects in the prior art, the invention aims to provide a method for recycling panthenol mother liquor. The method successfully realizes the recovery of pantolactone and 3-aminopropanol from panthenol mother liquor and has higher yield.
In order to achieve the purpose, the invention adopts the following technical scheme:
a method for recycling panthenol mother liquor, comprising the steps of:
(1) evaporating solvent in panthenol mother liquor to dryness, adding water to dissolve solute component, adjusting pH to alkaline with calcium hydroxide, reacting at 80-85 deg.C (such as 80 deg.C, 81 deg.C, 82 deg.C, 83 deg.C, 84 deg.C or 85 deg.C), cooling and precipitating after reaction, and separating to obtain calcium pantoate filter cake and filtrate containing 3-aminopropanol;
(2) mixing the calcium pantoate filter cake with sulfuric acid, reacting at 80-85 deg.C (such as 80 deg.C, 81 deg.C, 82 deg.C, 83 deg.C, 84 deg.C or 85 deg.C) while maintaining the temperature, adding alkaline calcium-containing compound into the reaction solution after the reaction to precipitate calcium ions, and separating to obtain calcium sulfate filter cake and pantoate lactone-containing filtrate.
In the art, pantolactone and 3-aminopropanol are generally used as raw materials, and are reacted in a solvent to synthesize panthenol, a reaction solution is cooled and crystallized to separate out panthenol crystals, and a filtrate obtained after solid-liquid separation is panthenol mother liquor, which contains unreacted raw materials of pantolactone and 3-aminopropanol, uncrystallized panthenol and solvents (such as methanol, ethanol and the like).
In the step (1), calcium hydroxide is used for hydrolyzing panthenol into pantoic acid lactone and 3-aminopropanol, and meanwhile, the pantoic acid lactone is converted into calcium pantoate precipitate with low solubility; in the step (2), calcium pantoate is converted into pantoic acid lactone by sulfuric acid, and redundant sulfuric acid is converted into calcium sulfate precipitate by using a basic calcium-containing compound. The method realizes the recovery of pantolactone and 3-aminopropanol from the panthenol mother liquor.
In some embodiments of the invention, the mass ratio of water to solute components in step (1) is 3-5: 1; for example, it may be 3:1, 3.2:1, 3.5:1, 3.8:1, 4:1, 4.2:1, 4.5:1, 4.8:1 or 5: 1.
In some embodiments of the invention, the pH is adjusted to 10-13 in step (1); for example, 10, 10.5, 11, 11.5, 12, 12.5, 13, etc.
In some embodiments of the invention, the reaction in step (1) is carried out for a time ranging from 1 to 3 hours; for example, it may be 1h, 1.2h, 1.5h, 1.8h, 2h, 2.2h, 2.5h, 2.8h, 3h, or the like.
In some embodiments of the invention, the temperature of the precipitation in step (1) is 20-30 ℃; for example, the temperature may be 20 ℃, 22 ℃, 23 ℃, 25 ℃, 26 ℃, 28 ℃ or 30 ℃.
In some embodiments of the invention, after the calcium pantoate filter cake is mixed with sulfuric acid in step (2), the pH of the resulting mixture is 1 to 1.5; for example, it may be 1, 1.1, 1.2, 1.3, 1.4, 1.5, etc.
In some embodiments of the invention, the reaction in step (2) is carried out for a time ranging from 1 to 3 hours; for example, it may be 1h, 1.2h, 1.5h, 1.8h, 2h, 2.2h, 2.5h, 2.8h, 3h, or the like.
In some embodiments of the present invention, after the reaction in step (2) is finished, the temperature is reduced to 20-30 ℃; for example, the temperature may be 20 ℃, 22 ℃, 23 ℃, 25 ℃, 26 ℃, 28 ℃ or 30 ℃.
In some embodiments of the invention, basic calcium-containing compound is added in step (2) to a pH of the reaction solution of 6.5-7; for example, it may be 6.5, 6.6, 6.7, 6.8, 6.9, 7, etc.
In some embodiments of the invention, the basic calcium-containing compound is selected from one or more of calcium hydroxide, calcium oxide, calcium carbonate and calcium bicarbonate.
In some embodiments of the invention, the method further comprises: and evaporating the filtrate containing the 3-aminopropanol to dryness, and rectifying to obtain the 3-aminopropanol.
In some embodiments of the invention, the method further comprises: and evaporating the filtrate containing the pantolactone to dryness to obtain the pantolactone.
In some embodiments of the invention, the method comprises the steps of:
(1) evaporating the solvent in the panthenol mother liquor to dryness, adding water to redissolve solute components, adjusting pH to 10-13 with calcium hydroxide, reacting at 80-85 deg.C for 1-3h, cooling to 20-30 deg.C after reaction, precipitating, and separating to obtain calcium pantoate filter cake and filtrate containing 3-aminopropanol;
(2) mixing the calcium pantoate filter cake with sulfuric acid to obtain a mixed solution, keeping the pH of the mixed solution at 1-1.5, reacting at 80-85 ℃ for 1-3h, cooling to 20-30 ℃ after the reaction is finished, adjusting the pH of the reaction solution to 6.5-7 by using calcium hydroxide to precipitate calcium ions, and separating to obtain a calcium sulfate filter cake and a filtrate containing pantoic acid lactone;
evaporating the filtrate containing the pantolactone to dryness to obtain the pantolactone;
and evaporating the filtrate containing the 3-aminopropanol to dryness and rectifying to obtain the 3-aminopropanol.
Compared with the prior art, the invention has the following beneficial effects:
according to the method, firstly, calcium hydroxide is used for hydrolyzing panthenol into pantoic acid lactone and 3-aminopropanol, meanwhile, pantoic acid lactone is converted into pantoic acid calcium precipitate with low solubility, then sulfuric acid is used for converting pantoic acid calcium into pantoic acid lactone, redundant sulfuric acid is converted into calcium sulfate precipitate by using an alkaline calcium-containing compound, so that pantoic acid lactone and 3-aminopropanol are successfully recovered from a panthenol mother liquor, the yield of pantoic acid lactone reaches over 90%, and the yield of 3-aminopropanol reaches over 81%.
Detailed Description
The technical solution of the present invention is further explained by the following embodiments. It should be understood by those skilled in the art that the specific embodiments are only for the understanding of the present invention and should not be construed as the specific limitations of the present invention.
The panthenol mother liquor used in the examples of the present invention had the following composition:
0.3 wt% of DL-pantolactone, 0.2 wt% of 3-aminopropanol, 5 wt% of DL-panthenol and the balance of methanol as a solvent.
Example 1
The embodiment provides a method for recycling panthenol mother liquor, which comprises the following steps:
(1) evaporating methanol in DL-panthenol mother liquor to dryness for recovery, taking 200g of solute components, adding 600g of water for redissolving, adjusting the pH to 11 by using calcium hydroxide, carrying out heat preservation reaction for 2 hours at 83 ℃, cooling to 25 ℃ after the reaction is finished, carrying out precipitation, and filtering to obtain a calcium pantoate filter cake and a filtrate containing 3-aminopropanol;
(2) adding a sulfuric acid solution into the calcium pantoate filter cake to obtain a mixed solution with the pH of 1, carrying out heat preservation reaction at 83 ℃ for 2 hours, cooling to 25 ℃ after the reaction is finished, adjusting the pH of the reaction solution to 6.7 by using calcium hydroxide to precipitate calcium ions, and filtering to obtain a calcium sulfate filter cake and a filtrate containing pantoic acid lactone;
evaporating the filter liquor containing the pantolactone to dryness to obtain 122.3g of pantolactone;
and evaporating the filtrate containing the 3-aminopropanol to dryness, and rectifying to obtain 63.1g of 3-aminopropanol.
Example 2
The embodiment provides a method for recycling panthenol mother liquor, which comprises the following steps:
(1) evaporating methanol in DL-panthenol mother liquor to dryness for recovery, taking 200g of solute components, adding 1000g of water for redissolution, adjusting the pH to 10 by using calcium hydroxide, carrying out heat preservation reaction for 1h at 85 ℃, cooling to 20 ℃ after the reaction is finished, carrying out precipitation, and filtering to obtain a calcium pantoate filter cake and a filtrate containing 3-aminopropanol;
(2) adding a sulfuric acid solution into the calcium pantoate filter cake to obtain a mixed solution with the pH of 1.3, carrying out heat preservation reaction for 1h at 85 ℃, cooling to 20 ℃ after the reaction is finished, adjusting the pH of the reaction solution to 6.5 by using calcium hydroxide to precipitate calcium ions, and filtering to obtain a calcium sulfate filter cake and a filtrate containing pantoic acid lactone;
evaporating the filtrate containing the pantolactone to dryness to obtain 121.1g of pantolactone;
and evaporating the filtrate containing the 3-aminopropanol to dryness, and rectifying to obtain 62.8g of 3-aminopropanol.
Example 3
The embodiment provides a method for recycling panthenol mother liquor, which comprises the following steps:
(1) evaporating methanol in DL-panthenol mother liquor to dryness for recovery, taking 200g of solute component, adding 800g of water for redissolving, adjusting pH to 13 by using calcium hydroxide, carrying out heat preservation reaction for 3h at 80 ℃, cooling to 30 ℃ after the reaction is finished, carrying out precipitation, and filtering to obtain a calcium pantoate filter cake and a filtrate containing 3-aminopropanol;
(2) adding a sulfuric acid solution into the calcium pantoate filter cake to obtain a mixed solution with the pH of 1.5, carrying out heat preservation reaction at 80 ℃ for 3 hours, cooling to 30 ℃ after the reaction is finished, adjusting the pH of the reaction solution to 7 by using calcium hydroxide to precipitate calcium ions, and filtering to obtain a calcium sulfate filter cake and a filtrate containing pantoic acid lactone;
evaporating the filtrate containing the pantolactone to dryness to obtain 116.8g of pantolactone;
and evaporating the filtrate containing the 3-aminopropanol to dryness, and rectifying to obtain 60.9g of 3-aminopropanol.
Example 4
This example provides a method for recycling a panthenol mother liquor, which is different from example 1 only in that the pH is adjusted to 9 with calcium hydroxide in step (1).
Example 5
This example provides a method for recycling a panthenol mother liquor, which is different from example 1 only in that the pH of the mixed solution after the sulfuric acid solution is added in step (2) is 2.5.
Comparative example 1
The comparative example provides a method for recycling panthenol mother liquor, which comprises the following specific steps:
(1) evaporating methanol in DL-panthenol mother liquor to dryness for recovery, taking 200g of solute component, adding 800g of water for redissolving, dropwise adding sulfuric acid to adjust the pH value to 1, keeping the temperature at 80 ℃, stirring l h, cooling to 30 ℃, adding sodium hydroxide to adjust the pH value to 5, and decolorizing and filtering with activated carbon to obtain decolorized filtrate;
(2) adding ethyl acetate into the obtained filtrate, extracting for 3 times, collecting ethyl acetate phase and water phase respectively, mixing ethyl acetate phase, and concentrating to obtain pantolactone 102.3 g;
(3) adjusting the pH of the water phase obtained in the step (2) to the isoelectric point of 3-aminopropanol by using a sodium hydroxide solution, then concentrating under reduced pressure until the water content is 30%, cooling to 0 ℃ for crystallization, filtering, and respectively recovering crystalline sodium sulfate and filtrate containing 3-aminopropanol;
(4) the filtrate of 3-aminopropanol was dehydrated under reduced pressure and then rectified to give 56.3g of 3-aminopropanol.
The purity of pantolactone and 3-aminopropanol recovered in the above examples and comparative examples was checked by liquid chromatography and gas chromatography, respectively, and the yield (initial mass based on the total mass of the component contained in the mother liquor of DL-panthenol and the component produced by complete hydrolysis of DL-panthenol) was calculated, and the results are shown in the following Table 1:
TABLE 1
As can be seen from Table 1, the method provided by the invention successfully realizes the recovery of pantolactone and 3-aminopropanol from the panthenol mother liquor, the yield of pantolactone reaches more than 90%, and the yield of 3-aminopropanol reaches more than 81%.
Among them, example 4 is inferior to example 1 in the purity and yield of pantolactone and 3-aminopropanol due to incomplete decomposition of panthenol caused by a lower pH in step (1). Example 5 the reaction of calcium pantoate with sulfuric acid was insufficient due to the higher pH in step (2), and the yield and purity of pantolactone obtained were reduced.
The method of comparative example 1 has insufficient hydrolysis of panthenol and low yields of pantolactone and 3-aminopropanol, and the method of comparative example 1 requires the use of a large amount of organic solvent, not only is the operation complicated and not environmentally friendly, but also the loss of pantolactone is large.
Although the invention has been described in detail hereinabove by way of general description, specific embodiments and experiments, it will be apparent to those skilled in the art that many modifications and improvements can be made thereto based on the invention. Accordingly, such modifications and improvements are intended to be within the scope of the invention as claimed.
Claims (10)
1. A method for recycling panthenol mother liquor, which is characterized by comprising the following steps:
(1) evaporating the solvent in the panthenol mother liquor to dryness, adding water to redissolve solute components, adjusting pH to be alkaline by using calcium hydroxide, carrying out heat preservation reaction at the temperature of 80-85 ℃, cooling and precipitating after the reaction is finished, and separating to obtain a calcium pantoate filter cake and a filtrate containing 3-aminopropanol;
(2) mixing the calcium pantoate filter cake with sulfuric acid, carrying out heat preservation reaction at the temperature of 80-85 ℃, adding an alkaline calcium-containing compound into a reaction solution after the reaction is finished to precipitate calcium ions, and separating to obtain a calcium sulfate filter cake and a filtrate containing pantoic acid lactone.
2. The method according to claim 1, wherein the mass ratio of the water to the solute component in step (1) is 3-5: 1;
preferably, the pH is adjusted to 10-13 in step (1).
3. The process according to claim 1 or 2, wherein the reaction time in step (1) is 1 to 3 hours.
4. A method according to any one of claims 1 to 3, wherein the temperature of the reduced temperature precipitate in step (1) is in the range of 20 to 30 ℃.
5. The method according to any one of claims 1 to 4, wherein the pH of the mixture obtained after mixing the calcium pantoate filter cake with sulfuric acid in step (2) is 1 to 1.5.
6. The process according to any one of claims 1 to 5, wherein the reaction time in step (2) is 1 to 3 hours.
7. The method according to any one of claims 1 to 6, wherein the temperature is reduced to 20 to 30 ℃ after the reaction in step (2) is completed.
8. A process according to any one of claims 1 to 7, characterized in that basic calcium-containing compound is added in step (2) to a pH of the reaction solution of 6.5 to 7;
preferably, the basic calcium-containing compound is selected from one or more of calcium hydroxide, calcium oxide, calcium carbonate and calcium bicarbonate.
9. The method according to any one of claims 1-8, further comprising: evaporating the filtrate containing the 3-aminopropanol to dryness, and rectifying to obtain the 3-aminopropanol;
preferably, the method further comprises: and evaporating the filtrate containing the pantolactone to dryness to obtain the pantolactone.
10. A method according to any of claims 1-9, characterized in that the method comprises the steps of:
(1) evaporating the solvent in the panthenol mother liquor to dryness, adding water to redissolve solute components, adjusting pH to 10-13 with calcium hydroxide, reacting at 80-85 deg.C for 1-3h, cooling to 20-30 deg.C after reaction, precipitating, and separating to obtain calcium pantoate filter cake and filtrate containing 3-aminopropanol;
(2) mixing the calcium pantoate filter cake with sulfuric acid to obtain a mixed solution, keeping the pH of the mixed solution at 1-1.5, reacting at 80-85 ℃ for 1-3h, cooling to 20-30 ℃ after the reaction is finished, adjusting the pH of the reaction solution to 6.5-7 by using calcium hydroxide to precipitate calcium ions, and separating to obtain a calcium sulfate filter cake and a filtrate containing pantoic acid lactone;
evaporating the filtrate containing the pantolactone to dryness to obtain the pantolactone;
and evaporating the filtrate containing the 3-aminopropanol to dryness and rectifying to obtain the 3-aminopropanol.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110845307A (en) * | 2019-11-28 | 2020-02-28 | 安徽泰格生物科技有限公司 | Method for recovering D-calcium pantothenate mother liquor |
| CN111484463A (en) * | 2020-05-22 | 2020-08-04 | 安徽安力肽生物科技有限公司 | Method for recycling panthenol mother liquor |
| CN111499602A (en) * | 2020-05-14 | 2020-08-07 | 吴江 | Method for extracting D-pantolactone from D L-pantolactone split liquid by calcium salt method |
| CN111748591A (en) * | 2019-03-29 | 2020-10-09 | 安徽华恒生物科技股份有限公司 | Production method of D-pantoic acid lactone |
| CN112209819A (en) * | 2020-09-27 | 2021-01-12 | 安徽泰格生物科技有限公司 | Preparation method of D-pantoic acid calcium |
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- 2021-12-29 CN CN202111647239.4A patent/CN114394948B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111748591A (en) * | 2019-03-29 | 2020-10-09 | 安徽华恒生物科技股份有限公司 | Production method of D-pantoic acid lactone |
| CN110845307A (en) * | 2019-11-28 | 2020-02-28 | 安徽泰格生物科技有限公司 | Method for recovering D-calcium pantothenate mother liquor |
| CN111499602A (en) * | 2020-05-14 | 2020-08-07 | 吴江 | Method for extracting D-pantolactone from D L-pantolactone split liquid by calcium salt method |
| CN111484463A (en) * | 2020-05-22 | 2020-08-04 | 安徽安力肽生物科技有限公司 | Method for recycling panthenol mother liquor |
| CN112209819A (en) * | 2020-09-27 | 2021-01-12 | 安徽泰格生物科技有限公司 | Preparation method of D-pantoic acid calcium |
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