CN1050356C - Process for preparing sodium (or potassium) L-ascorbate - Google Patents
Process for preparing sodium (or potassium) L-ascorbate Download PDFInfo
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- CN1050356C CN1050356C CN95119614A CN95119614A CN1050356C CN 1050356 C CN1050356 C CN 1050356C CN 95119614 A CN95119614 A CN 95119614A CN 95119614 A CN95119614 A CN 95119614A CN 1050356 C CN1050356 C CN 1050356C
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Abstract
The present invention relates to a preparation method of sodium (or potassium) L-ascorbate. A 2-keto-sodium colombate solid is prepared from fermentation liquid containing 2-keto-sodium gulonate as initial raw materials by the method of flocculation or ultrafiltration and esterified with methanol under an acid condition; esterifying liquid is neutralized, and the unreacted 2-keto-sodium gulonate is precipitated by adding bicarbonate; precipitated clear liquid is separated out and lactonized by adding bicarbonate; thus, the sodium (or potassium) L-ascorbate is prepared. The method removes the steps of large-scale ion exchange and protein removal by heating in the prior art, saves energy sources and auxiliary materials, reduces the production cost, shortens a production period and enables the yield to be improved by 5 to 18%.
Description
The present invention relates to produce the method for L-sodium ascorbate or potassium, especially a kind of is the method that starting raw material prepares L-sodium ascorbate or potassium with the fermented liquid that contains 2-ketone group-sodium colombate.
At present, ascorbate salt is to be feedstock production with the xitix, and xitix adopts sorbyl alcohol through two-step fermentation more, through fermentation, extract, transform, operation preparation such as refining.But the xitix of two step fermentation method productions has only 42-50% to the yield of raw material sorbyl alcohol, and relatively large sorbyl alcohol changes into other material and uncrystallized 2-ketone group-Gu Long acid and loses in fermented extracted 2-ketone group-Gu Long acid process.Simultaneously, the concentration of the 2-ketone group-sodium colombate in the fermented liquid only has 7-8%, need to transfer iso-electric point, heating removes albumen, walk ion exchange column twice, therefore the concentration of the 2-ketone group-Gu Long acid solution after the exchange is reduced to 4-6%, makes 2-ketone group-Gu Long acid through concentrating under reduced pressure, crystallization, separation, oven dry and needs tens hours long-time.And oversize by lactonize reaction times of preparation L-sodium ascorbate or potassium of 2-ketone group-methyl 2-keto-L-gulonate, generally also tens hours.This technology soda acid consumption is big, and the production cycle is long, and energy consumption is big, and intermediate destroys more, and equipment corrosion is serious, and yield is difficult to improve, and the total recovery from fermented liquid to L-sodium ascorbate or potassium also only has 70-78%.Participate in reaction as reaction system small part methyl alcohol, part methyl alcohol keeps temperature of reaction with the backflow form, and also having quite a few methyl alcohol is to remove the moisture content in the reaction system, so that the esterification balanced reaction is carried out to improve reactivity to the direction of resultant.But because the time is long, 2-ketone group-Gu Long acid or 2-ketone group-methyl 2-keto-L-gulonate, L-sodium ascorbate or potassium easily are thermal decomposited and destroy.The method for making (CN1048387A) of the patent L-sodium ascorbate of Switzerland En Kao company or potassium has been done a little improvement to esterification and lactonization reaction, has shortened the reaction times, but it is an initial reactant with 2-ketone group-Gu Long acid still.
The purpose of this invention is to provide a kind of production with fermented liquid in the process of L-sodium ascorbate or potassium, the reaction times of extracting intermediate 2-ketone group-sodium colombate and 2-ketone group-methyl 2-keto-L-gulonate generation 2-ketone group-methyl 2-keto-L-gulonate can be shortened, make L-sodium ascorbate or the potassium that reaches medical purity with economized form, the yield of producing L-sodium ascorbate or potassium is improved, reduce the cost of L-sodium ascorbate or potassium.
Purpose of the present invention can reach by following measure.
Preparation method of the present invention is a starting raw material with the fermented liquid that contains 2-ketone group-sodium colombate, as being that raw material is a starting raw material through the fermented liquid of two-step fermentation production with the sorbyl alcohol.At first remove the protein in the fermented liquid, the solution behind the isolating protein makes intermediate 2-ketone group-sodium colombate through concentrating under reduced pressure, crystallization, separation, drying successively, and its purity can reach more than the 90-%.2-ketone group-sodium colombate is dissolved in methanol solution and the concentrated sulfuric acid solution, 2-ketone group-sodium colombate makes 2-ketone group-methyl 2-keto-L-gulonate with methanol esterification under acidic conditions, add supercarbonate again, so that no esterification 2-ketone group-Gu Long acid and the intact vitriol oil salify of unreacted are precipitated out from solution together with other impurity, its add-on is neutralisation of sulphuric acid and unreacted 2-ketone group-Gu Long acid (accounting for 6-8%) aequum, and 2-ketone group-methyl 2-keto-L-gulonate is lactonized.Tell precipitation then, in telling the clear liquid that post precipitation stays, add sodium bicarbonate or saleratus again, wherein contained 2-ketone group-methyl 2-keto-L-gulonate is lactonized, generate L-sodium ascorbate or potassium suspension in reaction solution, L-sodium ascorbate or the potassium that lactonizes and produce is told in cooling, use methanol wash, promptly make product of the present invention.
Except that protein in the fermented liquid can adopt flocculation or hyperfiltration process.When adopting flucculation process, but flocculation agent is a kind of in chitin, sodium laurylsulfonate, improvement polyacrylamide, yellow prussiate of potash, alum, the vitriol etc. or several.The add-on of flocculation agent is the 0.2%-0.4% of starting raw material weight, flocculation temperature 10-45 ℃, flocculation time 0.5-2 hour, through the concentrating under reduced pressure post crystallization under habitual concentrating under reduced pressure temperature in present technique field and Tc of the solution behind the flocculation isolating protein, carry out solid-liquid separation again, promptly get intermediate 2-ketone group-sodium colombate, purity is more than 90%, and yield can reach 92.10%.
If adopt the method for ultrafiltration isolating protein, then the molecular weight cut-off 3-10 ten thousand of ultra-filtration membrane is more suitable, ultrafiltrated is being no more than concentrating under reduced pressure under 50 ℃ of conditions, preferred concentration ratio is 1: 13-1: 20, be cooled to 0 ℃ of crystallization then, separate making 2-ketone group-sodium colombate, purity reaches more than 92%, and yield can reach 84.6%.
In the esterification technological process, 2-ketone group-sodium colombate is dissolved in the methanol solution, carries out esterification reaction of organic acid and make 2-ketone group-methyl 2-keto-L-gulonate under the vitriol oil effect that plays catalysis and reactivity.The weight ratio of 2-ketone group-sodium colombate and methanol solution consumption is 1: 2-1: 5, and the weight ratio of 2-ketone group-sodium colombate and vitriol oil consumption is 1: 2-1: 4, esterification was carried out 1-2 hour, and temperature of reaction 60-70 ℃, gamma value reaches 88-92%.
In the solution after esterification, can be chosen under the condition that is no more than 55 ℃, add in order in and the supercarbonate of the vitriol oil and the 2-ketone group-Gu Long acid of failing to react, finish and be warming up to 60-70 ℃, reaction times 0.5-2 hour, tell precipitation then.
Telling precipitation is preferable methods with the filtered while hot, and the gained precipitation is washed with the vitriol oil and methanol solution, and washing lotion merges, and can be reused in the above-mentioned esterification, so that contained 2-ketone group-sodium colombate esterification in the precipitation improves yield.
Tell in the post precipitation gained clear liquid, when adding sodium bicarbonate or saleratus again, be preferably under the 60-70 ℃ of temperature backflow 1-2 hour, so that wherein contained 2-ketone group-methyl 2-keto-L-gulonate lactonizes, generate L-sodium ascorbate or potassium and be suspended in the reaction solution, be cooled to 0-10 ℃, kept 10-40 minute, isolate L-SODIUM ASCORBATE or sylvite, make L-sodium ascorbate or potassium through methanol wash again.
The fermented liquid that utilization of the present invention contains 2-ketone group-sodium colombate direct preparation 2-ketone group-sodium colombate behind flocculation or ultrafiltration isolating protein makes L-sodium ascorbate or potassium through the method for improvement through lactonizing of 1-2 hour esterification, 0.5-2 hour again.The present invention has removed in the existing production technique and has transferred iso-electric point, the heating isolating protein, twice processing step such as ion exchange column exchange, reduce the consumption and the kind of subsidiary material such as soda acid, a large amount of energy and personnel have been saved, this step of ion exchange liquid concentrating under reduced pressure only, just can save the energy of 30-40%, overcome the heavy corrosion of 2-ketone group-Gu Long acid to equipment, saved the one-time construction investment simultaneously, production cycle is shortened dramatically, improve production efficiency, reduced intermediates such as 2-ketone group-Gu Long acid or its methyl esters and destroyed and energy consumption, reduced production cost, make yield improve 5-18%, can reach more than the 90-98%.
Accompanying drawing 1 is process flow diagram of the present invention.
Describe the present invention in detail below in conjunction with embodiment.
Embodiment 1.
Referring to accompanying drawing 1,800ml with sorbyl alcohol in the fermented liquid that two-step fermentation is produced (every milliliter of fermented liquid contains 61.41 milligrams of 2-ketone group-sodium colombates), add flocculation agent chitin 1.6 grams and gac 2 grams, stirring at room 0.5 hour is filtered, and transparent filtrate is concentrating under reduced pressure under 45 ℃ of temperature, be cooled to 2 ℃ of crystallizations then, filter, precipitation vacuum-drying, purity is intermediate 2-ketone group-sodium colombate white crystals powder 43.4 grams of 90.3%.
Get by this routine method for preparing, the intermediate 2-ketone group of purity average out to 91.79%-sodium colombate white powder crystallization 50 grams, add 165 ml methanol, 8 milliliters of vitriol oils (content 98%), 60-70 ℃ of stirring refluxed 2 hours down, be cooled to 27 ℃, add 4.5 gram sodium bicarbonates, finish and be warming up to 64 ℃, continue to stir 2 hours, filter, must precipitate 17.5 grams (doing).Under agitation add 22.0 gram sodium bicarbonates in filtrate, under 60-70 ℃ of temperature, refluxed 1 hour, be cooled to 4 ℃, 20 minutes after-filtration, precipitation after the drying purity is that 83.28% L-sodium ascorbate 45.5 restrains, one time yield is 90.13%.
Embodiment 2.
Referring to accompanying drawing 1, get 100 liters of fermented liquids (every milliliter of fermented liquid contains 60.98 milligrams of 2-ketone group-sodium colombates) of producing through two-step fermentation with sorbyl alcohol through board-like membrane ultrafiltration, the molecular weight cut-off 30,000 of film, get high-quality transparent 2-ketone group-sodium colombate solution, (concentration ratio of ultrafiltration is 1: 15, and every milliliter contains 61.76 milligrams of 2-ketone group-sodium colombates in 93.8 liters the ultrafiltrated).Be cooled to 5 ℃ of crystallizations behind concentrating under reduced pressure, separate, vacuum-drying gets the 2-ketone group-5.72 kilograms in sodium colombate powder again, purity 90.2%, total recovery are 84.6%.
With 17.57 grams of the precipitation that contains 2-ketone group-sodium colombate after the esterification among the embodiment 1, add 9 milliliters of the vitriol oils, 60 milliliters of methyl alcohol stir, 10 minutes after-filtration, precipitation is washed with 100 ml methanol methods, and filtrate and washing lotion merge stand-by.
Get by this routine method for preparing, 2-ketone group-sodium colombate 50 grams of purity average out to 91.2%, add above-mentioned amalgamation liquid, stir down and refluxed 2 hours at 65 ℃, add 5.5 gram sodium bicarbonates when being cooled to 50 ℃, finish and be warming up to 0.5 hour after-filtration of 70 ℃ of stirrings, must precipitate 17.8 grams (doing), filtrate under agitation adds 22.5 gram sodium bicarbonates, and 60-70 ℃ was refluxed 1 hour, be cooled to 5 ℃, 30 minutes after-filtration get product, and dry back product weighs 47.6 grams, 83.99%, yield of purity is 95.71%.
Embodiment 3.
Get 100 liters of fermented liquid (content: 2-ketone group-sodium colombate 62.38 mg/ml) of producing through two-step fermentation with sorbyl alcohol, through the super liquid of board-like film, the molecular weight cut-off 100,000 of film, get 94.7 liters of the solution (content 62.10 mg/ml, the concentration ratio of ultrafiltration are 1: 18) of transparent 2-ketone group-sodium colombate, behind concentrating under reduced pressure, be cooled to 5 ℃ of crystallizations, separate again, vacuum-drying gets 5.82 kilograms of 2-ketone groups-sodium colombate powder, and purity 91.0%, total recovery are 84.8%.
Get by this routine method for preparing, 2-ketone group-sodium colombate 50 grams of purity average out to 91.79%, add 200 ml methanol, 8 milliliters of vitriol oils, 60-70 ℃ of stirring refluxed 2 hours down, be cooled to 45 ℃, add saleratus 5.4 grams, finish and be warming up to 65 ℃, continue to stir 2 hours, filter, must precipitate 21.5 grams (doing).Under agitation add 26.2 gram saleratus in filtrate, refluxed 1 hour, be cooled to 2 ℃ at 60-70 ℃, 30 minutes after-filtration, after the precipitation drying purity is 85.10% L-potassium ascorbate 48.1g, one time yield is 90.02%.
Embodiment 4.
Get 100 milliliters of fermented liquids (2-ketone group-sodium colombate 61.41 mg/ml), add flocculation agent sodium laurylsulfonate 3 grams and improvement polyacrylamide 1 gram, 58 ℃ flocculated 110 minutes, filter, clear liquid is being no more than concentrating under reduced pressure under 45 ℃ of temperature, be cooled to 8 ℃ of crystallizations again, crystallization is dry after filtration, makes purity and be intermediate 2-ketone group-sodium colombate 55.21 grams of 90.1%.
Get by this routine method for preparing, 2-ketone group-sodium colombate 100 grams of purity average out to 91.4%, add 555 ml methanol, 19 milliliters of vitriol oils, 60-70 ℃ of stirring refluxed 75 minutes down, be cooled to 50 ℃, add 10.7 gram sodium bicarbonates, finish and be warming up to 64-68 ℃, continue to stir 0.5 hour, filter, must precipitate 35.4 grams, under agitation add 44.3 gram sodium bicarbonates in filtrate, 60-70 ℃ was refluxed 2 hours down, be cooled to 8 ℃, kept 40 minutes, precipitation after the drying purity is 84.2% L-sodium ascorbate 89.5 grams.
Claims (13)
1, the preparation method of a kind of L-sodium ascorbate or potassium is included in the sulfuric acid existence and forms 2-ketone group-methyl 2-keto-L-gulonate with methanol esterification down, lactonizes by adding sodium bicarbonate or saleratus again, it is characterized in that comprising successively following processing step:
(1) be starting raw material with the fermented liquid that contains 2-ketone group-sodium colombate, remove the protein in the fermented liquid,
(2) solution behind the isolating protein makes intermediate 2-ketone group-sodium colombate through concentrating under reduced pressure, crystallization, separation, drying successively,
(3) 2-ketone group-sodium colombate is dissolved in methanol solution and the concentrated sulfuric acid solution, makes 2-ketone group-methyl 2-keto-L-gulonate,
(4) add sodium bicarbonate or saleratus, no esterification 2-ketone group-Gu Long acid and the intact vitriol oil salify of unreacted are precipitated out from solution, its add-on be in and the vitriol oil and the 2-ketone group of failing to react-Gu Long acid aequum, and 2-ketone group-methyl 2-keto-L-gulonate is lactonized
(5) tell precipitation,
(6) in telling the liquid of post precipitation, add sodium bicarbonate or saleratus, wherein contained 2-ketone group-methyl 2-keto-L-gulonate lactonized,
(7) cooling is told the L-sodium ascorbate or the L-potassium ascorbate that lactonize and produce, and is used methanol wash.
2, preparation method according to claim 1 is characterized in that removing protein in the fermented liquid by flocculation or hyperfiltration process.
3, preparation method according to claim 2, it is characterized in that the isolating protein flocculation agent is chitin, dodecyl sodium iodate, improvement polyacrylamide, yellow prussiate of potash, alum or vitriol, its add-on is the 0.2-0.4% of starting raw material weight, flocculation temperature 10-60 ℃, flocculation time 0.5～2 hour, solution behind the flocculation isolating protein is concentrating under reduced pressure post crystallization, solid-liquid separation again under habitual concentrating under reduced pressure temperature in present technique field and Tc.
4, preparation method according to claim 2 is characterized in that the molecular weight cut-off 3-10 ten thousand of ultra-filtration membrane, and concentration ratio is 1: 13～1: 20.
5, according to the described preparation method of any claim in the claim 1 to 4, the weight ratio that it is characterized in that 2-ketone group-sodium colombate and methanol solution consumption is 1: 2～1 :-5, with the weight ratio of vitriol oil consumption be 1: 2～1: 4, esterification 1-2 hour, 60～70 ℃ of temperature of reaction.
6, according to the described preparation method of any claim in the claim 1 to 4, it is characterized in that adding in order in and temperature during the supercarbonate of the vitriol oil and the 2-ketone group-Gu Long acid of failing to react be no more than 55 ℃, finish and be warming up to 60-70 ℃ of reaction 0.5-2 hour, tell precipitation.
7, preparation method according to claim 5, it is characterized in that adding in order in and temperature during the supercarbonate of the vitriol oil and the 2-ketone group-Gu Long acid of failing to react be no more than 55 ℃, finish and be warming up to 60～70 ℃ of reactions 0.5～2 hour, tell precipitation.
8,, it is characterized in that washing lotion merges, and is reused in the esterification with the vitriol oil and methanol solution washing precipitation according to the described preparation method of any claim in the claim 1 to 4.
9, preparation method according to claim 7 is characterized in that washing lotion merges, and is reused in the esterification with the vitriol oil and methanol solution washing precipitation.
10, according to the described preparation method of any claim in the claim 1 to 4, it is characterized in that in telling the clear liquid of post precipitation, add sodium bicarbonate or saleratus, under 60-70 ℃ of temperature backflow 1-2 hour, wherein contained 2-ketone group-methyl 2-keto-L-gulonate is lactonized.
11, preparation method according to claim 9 is characterized in that in telling the solution of post precipitation, adds sodium bicarbonate or saleratus, under 60-70 ℃ of temperature backflow 1--2 hour, wherein contained 2-ketone group-methyl 2-keto-L-gulonate is lactonized.
12, according to the described preparation method of any claim in the claim 1 to 4, the reaction solution after it is characterized in that lactonizing is cooled to 0-10 ℃, keeps 10-40 minute, isolates L-SODIUM ASCORBATE or sylvite again and uses methanol wash.
13, preparation method according to claim 11, the reaction solution after it is characterized in that lactonizing is cooled to 0-10 ℃, keeps 10-40 minute, isolates L-SODIUM ASCORBATE or sylvite again and uses methanol wash.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN95119614A CN1050356C (en) | 1995-11-24 | 1995-11-24 | Process for preparing sodium (or potassium) L-ascorbate |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN95119614A CN1050356C (en) | 1995-11-24 | 1995-11-24 | Process for preparing sodium (or potassium) L-ascorbate |
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| Publication Number | Publication Date |
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| CN1130627A CN1130627A (en) | 1996-09-11 |
| CN1050356C true CN1050356C (en) | 2000-03-15 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN95119614A Expired - Fee Related CN1050356C (en) | 1995-11-24 | 1995-11-24 | Process for preparing sodium (or potassium) L-ascorbate |
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Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101353337B (en) * | 2008-09-08 | 2011-04-06 | 陈星� | Vitamin c clean production method |
| CN101805319B (en) * | 2010-04-21 | 2012-09-26 | 石药集团维生药业（石家庄）有限公司 | Method for directly converting and preparing sodium ascorbate by using sodium gulonic acid |
| CN102424695A (en) * | 2011-10-28 | 2012-04-25 | 安徽泰格生物技术股份有限公司 | Sodium methyl gulonate and preparation method thereof |
| CN106047954B (en) * | 2016-07-29 | 2020-01-07 | 河南金丹乳酸科技股份有限公司 | Method for producing lactic acid and co-producing protein feed through circulating fermentation |
| CN106244638B (en) * | 2016-07-29 | 2020-01-07 | 河南金丹乳酸科技股份有限公司 | Comprehensive utilization process for producing lactic acid by biomass circulating fermentation |
| CN106632173A (en) * | 2016-12-28 | 2017-05-10 | 李玉成 | K2(C6H7O6)(HSO4) as well as preparation method and application thereof |
| CN106699704A (en) * | 2016-12-28 | 2017-05-24 | 李玉成 | Hydrogen sulfate sodium ascorbate as well as preparation method and application thereof |
| CN106632171A (en) * | 2016-12-28 | 2017-05-10 | 李玉成 | Silicon ascorbic acid and preparation method and application thereof |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0091134A2 (en) * | 1982-04-09 | 1983-10-12 | Shionogi & Co., Ltd. | Process for preparing L-ascorbic acid |
| CN1048387A (en) * | 1989-06-26 | 1991-01-09 | 恩考工程库尔公司 | L-sodium ascorbate or potassium method for making |
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1995
- 1995-11-24 CN CN95119614A patent/CN1050356C/en not_active Expired - Fee Related
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0091134A2 (en) * | 1982-04-09 | 1983-10-12 | Shionogi & Co., Ltd. | Process for preparing L-ascorbic acid |
| CN1048387A (en) * | 1989-06-26 | 1991-01-09 | 恩考工程库尔公司 | L-sodium ascorbate or potassium method for making |
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