CN114195752A - Environment-friendly d-alpha-tocopherol succinate refining preparation process - Google Patents
Environment-friendly d-alpha-tocopherol succinate refining preparation process Download PDFInfo
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- CN114195752A CN114195752A CN202210040849.6A CN202210040849A CN114195752A CN 114195752 A CN114195752 A CN 114195752A CN 202210040849 A CN202210040849 A CN 202210040849A CN 114195752 A CN114195752 A CN 114195752A
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- China
- Prior art keywords
- alpha
- tocopherol succinate
- tocopherol
- water
- succinate
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- GVJHHUAWPYXKBD-UHFFFAOYSA-N d-alpha-tocopherol Natural products OC1=C(C)C(C)=C2OC(CCCC(C)CCCC(C)CCCC(C)C)(C)CCC2=C1C GVJHHUAWPYXKBD-UHFFFAOYSA-N 0.000 title claims abstract description 90
- IELOKBJPULMYRW-NJQVLOCASA-N D-alpha-Tocopheryl Acid Succinate Chemical compound OC(=O)CCC(=O)OC1=C(C)C(C)=C2O[C@@](CCC[C@H](C)CCC[C@H](C)CCCC(C)C)(C)CCC2=C1C IELOKBJPULMYRW-NJQVLOCASA-N 0.000 title claims abstract description 71
- 229940099418 d- alpha-tocopherol succinate Drugs 0.000 title claims abstract description 67
- 238000007670 refining Methods 0.000 title claims abstract description 15
- 238000002360 preparation method Methods 0.000 title claims abstract description 8
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims abstract description 43
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 38
- 229960000984 tocofersolan Drugs 0.000 claims abstract description 23
- 239000002076 α-tocopherol Substances 0.000 claims abstract description 23
- 235000004835 α-tocopherol Nutrition 0.000 claims abstract description 23
- GVJHHUAWPYXKBD-IEOSBIPESA-N α-tocopherol Chemical compound OC1=C(C)C(C)=C2O[C@@](CCC[C@H](C)CCC[C@H](C)CCCC(C)C)(C)CCC2=C1C GVJHHUAWPYXKBD-IEOSBIPESA-N 0.000 claims abstract description 23
- 239000007787 solid Substances 0.000 claims abstract description 19
- 238000001816 cooling Methods 0.000 claims abstract description 16
- 238000001035 drying Methods 0.000 claims abstract description 16
- 239000007788 liquid Substances 0.000 claims abstract description 15
- 238000001914 filtration Methods 0.000 claims abstract description 14
- 238000004108 freeze drying Methods 0.000 claims abstract description 14
- 239000002904 solvent Substances 0.000 claims abstract description 13
- 239000000843 powder Substances 0.000 claims abstract description 12
- FALRKNHUBBKYCC-UHFFFAOYSA-N 2-(chloromethyl)pyridine-3-carbonitrile Chemical compound ClCC1=NC=CC=C1C#N FALRKNHUBBKYCC-UHFFFAOYSA-N 0.000 claims abstract description 10
- 238000000926 separation method Methods 0.000 claims abstract description 10
- 229940014800 succinic anhydride Drugs 0.000 claims abstract description 10
- IDGUHHHQCWSQLU-UHFFFAOYSA-N ethanol;hydrate Chemical compound O.CCO IDGUHHHQCWSQLU-UHFFFAOYSA-N 0.000 claims abstract description 8
- 238000010438 heat treatment Methods 0.000 claims abstract description 7
- 238000005886 esterification reaction Methods 0.000 claims abstract description 5
- 238000002156 mixing Methods 0.000 claims abstract description 3
- 238000000034 method Methods 0.000 claims description 14
- 238000003756 stirring Methods 0.000 claims description 9
- 238000006243 chemical reaction Methods 0.000 claims description 3
- 239000002994 raw material Substances 0.000 claims description 3
- 239000012141 concentrate Substances 0.000 claims 2
- 230000032050 esterification Effects 0.000 claims 1
- 239000003960 organic solvent Substances 0.000 abstract description 11
- 238000002425 crystallisation Methods 0.000 abstract description 5
- 230000008025 crystallization Effects 0.000 abstract description 5
- 239000000428 dust Substances 0.000 abstract description 5
- 238000005516 engineering process Methods 0.000 abstract description 3
- 230000006866 deterioration Effects 0.000 abstract description 2
- 230000001590 oxidative effect Effects 0.000 abstract description 2
- 231100000419 toxicity Toxicity 0.000 abstract description 2
- 230000001988 toxicity Effects 0.000 abstract description 2
- 230000002349 favourable effect Effects 0.000 abstract 1
- 239000000047 product Substances 0.000 description 16
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 description 6
- VLKZOEOYAKHREP-UHFFFAOYSA-N n-Hexane Chemical compound CCCCCC VLKZOEOYAKHREP-UHFFFAOYSA-N 0.000 description 6
- 238000004090 dissolution Methods 0.000 description 4
- 239000007789 gas Substances 0.000 description 3
- 231100000053 low toxicity Toxicity 0.000 description 3
- 239000010815 organic waste Substances 0.000 description 3
- 239000003208 petroleum Substances 0.000 description 3
- 230000009286 beneficial effect Effects 0.000 description 2
- 238000003912 environmental pollution Methods 0.000 description 2
- 238000005054 agglomeration Methods 0.000 description 1
- 230000002776 aggregation Effects 0.000 description 1
- 238000009835 boiling Methods 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 238000003889 chemical engineering Methods 0.000 description 1
- 239000011362 coarse particle Substances 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 239000012467 final product Substances 0.000 description 1
- 238000007710 freezing Methods 0.000 description 1
- 230000008014 freezing Effects 0.000 description 1
- 231100000086 high toxicity Toxicity 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
- 239000002912 waste gas Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D311/00—Heterocyclic compounds containing six-membered rings having one oxygen atom as the only hetero atom, condensed with other rings
- C07D311/02—Heterocyclic compounds containing six-membered rings having one oxygen atom as the only hetero atom, condensed with other rings ortho- or peri-condensed with carbocyclic rings or ring systems
- C07D311/04—Benzo[b]pyrans, not hydrogenated in the carbocyclic ring
- C07D311/58—Benzo[b]pyrans, not hydrogenated in the carbocyclic ring other than with oxygen or sulphur atoms in position 2 or 4
- C07D311/70—Benzo[b]pyrans, not hydrogenated in the carbocyclic ring other than with oxygen or sulphur atoms in position 2 or 4 with two hydrocarbon radicals attached in position 2 and elements other than carbon and hydrogen in position 6
- C07D311/72—3,4-Dihydro derivatives having in position 2 at least one methyl radical and in position 6 one oxygen atom, e.g. tocopherols
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Medicinal Preparation (AREA)
Abstract
The invention discloses an environment-friendly d-alpha-tocopherol succinate refining preparation process, which comprises the following steps: carrying out esterification reaction on S1 d-alpha-tocopherol and succinic anhydride to obtain d-alpha-tocopherol succinate, heating and dissolving the d-alpha-tocopherol succinate by using ethanol, cooling the d-alpha-tocopherol succinate, keeping the temperature below 0 ℃, adding a proper amount of water, and cooling the d-alpha-tocopherol succinate; s2, carrying out solid-liquid separation, adding a proper amount of water into the separated solid, mixing uniformly, and filtering to obtain hydrous d-alpha-tocopherol succinate; s3 freeze-drying to obtain d-alpha-tocopherol succinate powder. According to the invention, ethanol-water is firstly used as an organic solvent to carry out crystallization and refining on d-alpha-tocopheryl succinate, and the toxicity of the solvent is low; after solid-liquid separation, water is adopted to replace residual ethanol in the solid, so that only water is discharged in the drying process, and no organic solvent is discharged; and the subsequent freeze drying technology is adopted, so that the product is in a loose powder form, the subsequent crushing step is not needed, the generation of dust is reduced, and meanwhile, the low-temperature drying is favorable for reducing the oxidative deterioration of the product.
Description
Technical Field
The invention relates to the technical field of chemical engineering, in particular to an environment-friendly refining preparation process of d-alpha-tocopherol succinate.
Background
d-alpha-tocopherol succinate is crystalline solid powder, and the d-alpha-tocopherol succinate is generally prepared by esterification reaction of d-alpha-tocopherol serving as a raw material and succinic anhydride under the condition of a catalyst at present. After the reaction is finished, organic solvents such as n-hexane and petroleum ether are adopted for crystallization and refining. And (3) after crystallization, carrying out solid-liquid separation by adopting a plate frame or a centrifuge to obtain d-alpha-tocopherol succinate containing a solvent, then drying, drying the solvent by using an oven, a fluidized drying mode and other modes to obtain coarse-particle d-alpha-tocopherol succinate, and then crushing to obtain d-alpha-tocopherol succinate powder.
The above conventional processes have the following disadvantages:
1. organic solvents such as n-hexane and petroleum ether are adopted for crystallization, the organic solvents have high toxicity, a large amount of organic solvent waste gas is generated in the solid-liquid separation and drying processes, and the environmental pollution is great; in addition, organic solvent remains in the product and is harmful.
2. Drying the product by adopting drying modes such as an oven, fluidized drying and the like to generate organic waste gas, wherein the dried product is agglomerated and needs to be crushed subsequently, and dust is easily generated in the crushing process and is harmful to the dust.
3. The conventional drying modes such as an oven, boiling drying and the like are adopted, the temperature needs to reach 60 ℃, the melting point of the d-alpha-tocopheryl succinate is 73 ℃, and the high-temperature drying is easy to cause the product to deteriorate, yellow and agglomerate.
Disclosure of Invention
In order to solve the technical problems, the invention aims to provide an environment-friendly d-alpha-tocopherol succinate refining preparation process, wherein ethanol-water is used as a solvent to crystallize and refine the d-alpha-tocopherol succinate, and the d-alpha-tocopherol succinate is subsequently dried in a freezing mode, so that the environment-friendly performance is greatly improved.
Aiming at the problems, the invention adopts a technical scheme that: the provided environment-friendly d-alpha-tocopherol succinate refining preparation process comprises the following steps:
s1 d-alpha-tocopherol and succinic anhydride are subjected to esterification reaction to obtain d-alpha-tocopherol succinate, the d-alpha-tocopherol succinate is heated to 40-60 ℃ by ethanol to be dissolved, and is cooled and kept below 0 ℃, a proper amount of water is added, and the d-alpha-tocopherol succinate is cooled and kept below 0 ℃ for more than 24 hours;
s2, performing solid-liquid separation, adding a proper amount of water into the separated solid, uniformly mixing, and filtering to remove the ethanol-water solution as a solvent to obtain solid, namely the hydrous d-alpha-tocopherol succinate;
s3 freeze-drying to obtain d-alpha-tocopherol succinate powder.
According to the invention, ethanol-water is firstly used as an organic solvent to crystallize and refine d-alpha-tocopheryl succinate, and compared with the conventional technology, the solvent has low toxicity and small harm; after solid-liquid separation, residual ethanol in the solid is replaced by water, so that only water is discharged in the drying process, no organic solvent is discharged, and no organic solvent is left in the final product, thereby improving the safety of the product; by adopting the freeze drying technology, the product is in loose powder shape without agglomeration, the subsequent crushing step is not needed, the working procedures are reduced, the generation of dust is reduced, and meanwhile, the low-temperature drying is beneficial to reducing the oxidative deterioration of the product and improving the product quality.
Furthermore, the volume ratio of d-alpha-tocopherol succinate to ethanol in S1 is 1:5-7, and the ethanol is used as a solvent to crystallize the d-alpha-tocopherol succinate, so that the toxicity is greatly reduced compared with organic solvents such as n-hexane and petroleum ether.
Further, the volume ratio of the d-alpha-tocopherol succinate to the water in the S1 is 1:0.5-6, and the d-alpha-tocopherol succinate is precipitated by water in the step S1.
Furthermore, the volume ratio of the d-alpha-tocopherol succinate to the water in the S2 is 1:2-3, and the residual ethanol in the solid is replaced by the water in the step S2, so that only water is discharged in the subsequent process, and no ethanol remains.
Further, the conditions of freeze-drying in S3 are: the temperature is less than or equal to minus 5 ℃, and the vacuum degree is less than or equal to 1 Pa.
Further, in the S1, a d-alpha-tocopherol concentrated solution is used as a reaction raw material of d-alpha-tocopherol, and the mass content of d-alpha-tocopherol in the d-alpha-tocopherol concentrated solution is 80-95%.
Further, in the S1, d-alpha-tocopherol succinate is dissolved in ethanol and cooled, then water is slowly added dropwise at a speed of 1-10ml/min under a stirring state, and after the dropwise addition is completed, cooling is carried out for at least 24 hours.
The invention has the beneficial effects that:
1. low toxicity: ethanol-water is used as a solvent for crystallization and refining, and the solvent has low toxicity;
2. safety: after solid-liquid separation, residual ethanol is removed by adopting a water washing mode, so that no solvent residue exists in the subsequent process, the process safety is improved, and no ethanol residue exists in the product, so that the product safety is improved; the freeze drying mode is adopted, so that the subsequent crushing procedures are reduced, and the dust harm is greatly reduced;
3. environmental protection property: after solid-liquid separation, ethanol is replaced by water, so that organic waste gas is prevented from being generated in a drying process, and environmental pollution is avoided;
4. the cost is low: the ethanol in the solvent ethanol-water can be recycled, so that no organic waste gas is discharged basically, the loss is low, and the cost is low;
5. the effectiveness is as follows: the product content can be effectively improved from 80-95% to over 97%.
Detailed Description
The technical features and advantages of the invention are described in more detail below so that the advantages and features of the invention may be more readily understood by those skilled in the art, and thus, the scope of the invention will be more clearly and clearly defined.
Preferred embodiments of the present invention are described below. It should be understood by those skilled in the art that these embodiments are only for explaining the technical principle of the present invention, and are not intended to limit the scope of the present invention.
Example 1
Taking 100g of d-alpha-tocopherol concentrated solution (wherein the mass content of d-alpha-tocopherol is 87%), adding 25g of succinic anhydride, esterifying to obtain 120.2g of crude d-alpha-tocopherol succinate (the mass content of d-alpha-tocopherol succinate is 89.20%), adding 600ml of ethanol, heating to 60 ℃, cooling to 0 ℃ after complete dissolution, slowly adding 200ml of water, cooling for 24 hours, filtering out liquid, adding 200ml of water into solid, stirring uniformly, and filtering to obtain water-containing solid; freeze drying at-5 deg.C under 1Pa to obtain powder product 102.6g with d-alpha-tocopherol succinate content of 97.85%.
Example 2
Taking 100g of d-alpha-tocopherol concentrated solution (wherein the mass content of d-alpha-tocopherol is 80%), adding 25g of succinic anhydride, esterifying to obtain 118.6g of crude d-alpha-tocopherol succinate (wherein the mass content of d-alpha-tocopherol succinate is 83.14%), adding 700ml of ethanol, heating to 50 ℃, cooling to-5 ℃ after complete dissolution, slowly adding 50ml of water, cooling for 32 hours, filtering out liquid, adding 300ml of water into solid, stirring uniformly, and filtering to obtain water-containing solid; freeze drying at-8 deg.C under 1Pa to obtain powder product 92.1g with d-alpha-tocopherol succinate content of 97.62%.
Example 3
Taking 100g of d-alpha-tocopherol concentrated solution (wherein the mass content of d-alpha-tocopherol is 95%), adding 25g of succinic anhydride, esterifying to obtain 122.1g of crude d-alpha-tocopherol succinate (wherein the mass content of d-alpha-tocopherol succinate is 95.90%), adding 600ml of ethanol, heating to 45 ℃, completely dissolving, cooling to-3 ℃, slowly adding 600ml of water, cooling for 28 hours, filtering out liquid, adding 250ml of water into solid, uniformly stirring, and filtering to obtain water-containing solid; freeze drying at-6 deg.C under 1Pa to obtain powder product 111.2g with d-alpha-tocopherol succinate content of 98.94%.
Example 4
Taking 100g of d-alpha-tocopherol concentrated solution (wherein the mass content of d-alpha-tocopherol is 90%), adding 25g of succinic anhydride, esterifying to obtain 120.9g of crude d-alpha-tocopherol succinate (wherein the mass content of d-alpha-tocopherol succinate is 91.75%), adding 500ml of ethanol, heating to 40 ℃, cooling to 0 ℃ after complete dissolution, slowly adding 300ml of water, cooling for 36 hours, filtering out liquid, adding 200ml of water into solid, stirring uniformly, and filtering to obtain water-containing solid; freeze drying at-10 deg.c and 1Pa vacuum degree to obtain 105.5g product with d-alpha-tocopherol succinate content of 98.03%.
Example 5
Taking 100g of d-alpha-tocopherol concentrated solution (wherein the mass content of d-alpha-tocopherol is 92%), adding 25g of succinic anhydride, esterifying to obtain 121.1g of crude d-alpha-tocopherol succinate (wherein the mass content of d-alpha-tocopherol succinate is 93.40%), adding 700ml of ethanol, heating to 55 ℃, cooling to-2 ℃ after complete dissolution, slowly adding 400ml of water, cooling for 24 hours, filtering out liquid, adding 300ml of water into solid, stirring uniformly, and filtering to obtain water-containing solid; freeze drying at-7 deg.C under 1Pa to obtain powder product 106.3g with d-alpha-tocopherol succinate content of 98.22%.
The above description is only an embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications of equivalent structures and equivalent processes performed by the present invention or directly or indirectly applied to other related technical fields are included in the scope of the present invention.
Claims (8)
1. An environment-friendly d-alpha-tocopherol succinate refining preparation process is characterized by comprising the following steps:
s1 d-alpha-tocopherol and succinic anhydride are subjected to esterification reaction to obtain d-alpha-tocopherol succinate, the d-alpha-tocopherol succinate is heated to 40-60 ℃ by ethanol to be dissolved, the d-alpha-tocopherol succinate is cooled and kept below 0 ℃, a proper amount of water is added, and the d-alpha-tocopherol succinate is cooled and kept below 0 ℃ for more than 24 hours;
s2, carrying out solid-liquid separation, adding a proper amount of water into the separated solid, uniformly mixing, and filtering to remove a solvent ethanol-water solution to obtain hydrous d-alpha-tocopherol succinate;
s3 freeze-drying to obtain d-alpha-tocopherol succinate powder.
2. The process of claim 1, wherein the volume ratio of d-alpha-tocopheryl succinate to ethanol in S1 is 1: 5-7.
3. The process for refining and preparing d-alpha-tocopherol succinate according to claim 1, wherein the volume ratio of d-alpha-tocopherol succinate to water in S1 is 1: 0.5-6.
4. The process for refining and preparing d-alpha-tocopherol succinate according to claim 1, wherein the volume ratio of d-alpha-tocopherol succinate to water in S2 is 1: 2-3.
5. The process for refining and preparing d-alpha-tocopherol succinate according to claim 1, wherein the conditions for freeze-drying in the S3 are as follows: the temperature is less than or equal to minus 5 ℃, and the vacuum degree is less than or equal to 1 Pa.
6. The process for refining and preparing d-alpha-tocopherol succinate as claimed in claim 1, wherein a d-alpha-tocopherol concentrate is used as a reaction raw material of d-alpha-tocopherol in S1, and the mass content of d-alpha-tocopherol in the d-alpha-tocopherol concentrate is 80-95%.
7. The process according to claim 1 or 2, wherein in S1, the d- α -tocopherol succinate is dissolved in ethanol, cooled, and slowly added dropwise to water at a rate of 1 to 10ml/min while stirring.
8. An environment-friendly d-alpha-tocopherol succinate refining preparation process is characterized by comprising the following steps:
s1 esterification of d-alpha-tocopherol with succinic anhydride to obtain d-alpha-tocopherol succinate, heating to 40-60 deg.C with 5-7 times volume of ethanol to dissolve d-alpha-tocopherol succinate, cooling and maintaining at below 0 deg.C, adding 0.5-6 times volume of water to d-alpha-tocopherol succinate under stirring to precipitate d-alpha-tocopherol succinate, and cooling for at least 24 hr;
s2, carrying out solid-liquid separation, adding water with 2-3 times volume of d-alpha-tocopherol succinate into the obtained solid, stirring, and filtering to remove a solvent ethanol-water solution to obtain hydrous d-alpha-tocopherol succinate;
s3 freeze drying, cooling to below-5 deg.C, maintaining vacuum degree below 1Pa, and drying to obtain d-alpha-tocopherol succinate powder.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210040849.6A CN114195752A (en) | 2022-01-14 | 2022-01-14 | Environment-friendly d-alpha-tocopherol succinate refining preparation process |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202210040849.6A CN114195752A (en) | 2022-01-14 | 2022-01-14 | Environment-friendly d-alpha-tocopherol succinate refining preparation process |
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB866489A (en) * | 1959-12-31 | 1961-04-26 | Vitamins Ltd | Improvements in or relating to the preparation of a ús-ª--tocopherol derivative |
| GB1114150A (en) * | 1950-04-11 | 1968-05-15 | Eisai Co Ltd | Method of producing ª‡-tocopheryl acid succinate |
| EP0171009A2 (en) * | 1984-08-02 | 1986-02-12 | HENKEL CORPORATION (a Delaware corp.) | Purification of tocopherols by extraction |
| JP2008133275A (en) * | 2006-11-01 | 2008-06-12 | Api Corporation | Tocopherol glycoside and method for producing the same |
-
2022
- 2022-01-14 CN CN202210040849.6A patent/CN114195752A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1114150A (en) * | 1950-04-11 | 1968-05-15 | Eisai Co Ltd | Method of producing ª‡-tocopheryl acid succinate |
| GB866489A (en) * | 1959-12-31 | 1961-04-26 | Vitamins Ltd | Improvements in or relating to the preparation of a ús-ª--tocopherol derivative |
| EP0171009A2 (en) * | 1984-08-02 | 1986-02-12 | HENKEL CORPORATION (a Delaware corp.) | Purification of tocopherols by extraction |
| JP2008133275A (en) * | 2006-11-01 | 2008-06-12 | Api Corporation | Tocopherol glycoside and method for producing the same |
Non-Patent Citations (1)
| Title |
|---|
| 吴正红 等: "药剂学", 30 April 2020, 中国医药科技出版社, pages: 279 * |
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