CN101234962A - Technique for separating and purifying L-lactic acid - Google Patents
Technique for separating and purifying L-lactic acid Download PDFInfo
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- CN101234962A CN101234962A CNA2008100203975A CN200810020397A CN101234962A CN 101234962 A CN101234962 A CN 101234962A CN A2008100203975 A CNA2008100203975 A CN A2008100203975A CN 200810020397 A CN200810020397 A CN 200810020397A CN 101234962 A CN101234962 A CN 101234962A
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Abstract
The invention discloses a new technology for separating and purifying L-lactic acid with continuous ion exchange, membrane separation and molecular distillation. Centrifuged and decolorated lactic acid fermentation liquid is pumped into an ultrafiltration apparatus to remove proteins; clear liquid with a lactate concentration of 10-50g/L is then pumped into a continuous ion exchange system filled with anion exchange resin for adsorption; an inorganic salt solution with a concentration of 0.001-0.2M is used for impurity washing and an acid solution with a concentration of 0.1-2M is used for elution; nano-filtration technology is employed for synchronous concentration and desalination of the ion exchange eluent; high-purity and high-quality L-lactic acid can be obtained after treatment with molecular distillation means in the end. The technology has the advantages of low equipment investment, strong continuous operability, low production cost, high product purity, easy scale production, etc.
Description
Technical field
The present invention relates to the separation and preparation technology of high-purity L-lactic acid, belong to the biological products manufacture field.
Background technology
Lactic acid is a kind of important organic acid, at aspects such as food, medicine, chemical industry a lot of purposes is arranged, particularly can be as the monomer of synthesized degradable material poly(lactic acid) and be subjected to extensive concern.The lactic acid that uses on food and the medicine industry mainly adopts fermentative Production, when with fermentative Production lactic acid, traditional lactic acid separation method is: the lactic acid that produces that at first will ferment changes into calcium lactate, obtain lactic acid with calcium lactate and sulfuric acid reaction more subsequently, and make with extra care and form, in this process through decolouring, ion-exchange, technical process is long, operational condition is poor, the solid waste disposal difficulty the more important thing is that the yield of lactic acid generally has only 50～60% because calcium lactate has higher solubleness.In order to solve the problem that exists in traditional lactic acid separation method, there is part Study person to develop the technology of ion exchange method separating lactic acid recently.(ion exchange method is extracted the research of L-lactic acid novel process, Huaqiao University's journal [J], 1995 to old green moths etc., 16 (2), 231-234) adopt ion exchange resin (732 Zeo-karb) deliming, abandon assorted lactic acid, the extraction rate reached to 70% extracted through anionite-exchange resin again.Lee Shao Cheng (CN 1072210A) by pre-treatment, through gelatinization, fermentation, neutralization, press filtration, bleaching process, then by Zeo-karb, generates lactic acid with raw material.These methods have been abandoned the calcium lactate crystallisation process, have reduced working strength.But these methods are because the fixed bed switching technology that adopts at present, so resin demand is big, utilization ratio is low, the soda acid consumption of washing assorted agent, eluent, resin regeneration consumption is big, contaminate environment, and because the operation of single-column fractionation by adsorption, discharging concentration is low, water loss is big, can only periodical operation, and be not suitable for suitability for industrialized production and use.
Because the concentration of exchange operations can be too not high, so utilizing distillating method to need to increase a step concentration operation before preparing high-quality lactic acid, general all is the method that adopts evaporation, but, lactic acid goes bad because at high temperature easily decomposing, so the lactic acid quality that makes is generally not high, so a kind of technology that concentrates purpose that can reach at low temperatures of exigence.
Traditional technology adopts the distillation under vacuum separating lactic acid, but when common distillation under vacuum separates L-lactic acid, because operating system is difficult to the pressure that reaches lower, the distillatory temperature is higher relatively, makes the lactic acid thermotolerance that steams relatively poor, decomposes easily.Recently, partial monopoly has adopted molecular distillation technique to come fine purification of lactic acid, patent CN 1112345C and CN1161316C disclose a kind of short-path molecular distillation technology and a kind of method with short-path distillation and drum evaporator fine purification of lactic acid of lactic acid respectively, but because employing is rotation scraped film type molecular still, so it is bigger also to exist thickness of liquid film, heats is poor, feed liquid shortcomings the such as at high temperature residence time is long.
Summary of the invention
The novel process that the purpose of this invention is to provide a kind of separation and purification L-lactic acid.
The invention thinking: the present invention intend adopting continuous overcome from the friendship technology adopt that resin demand is big in the fixed bed switching technology, utilization ratio is low, wash assorted agent, soda acid consumption that eluent and resin regeneration consume is big, contaminate environment, discharging concentration is low, water loss big, can only periodical operation, be not suitable for the deficiency of suitability for industrialized production; Intend adopting membrane separation technique, utilize microfiltration membrane to remove macromolecular substance such as thalline and protein, utilize nanofiltration membrane to reach spissated purpose again; Plan has adopted molecular distillation technique to overcome the lactic acid poor heat resistance that traditional underpressure distillation goes out, labile shortcoming.Whole technology all is under the environment than low operating temperature, has played good guaranteeing role for the lactic acid for preparing high purity, good heat resistance.
For achieving the above object, the technical solution adopted in the present invention is as follows:
A kind of novel process of separation and purification L-lactic acid: will pump into ultrafiltration apparatus through L-lactic acid fermentation liquid centrifugal, decolouring and remove Deproteinization; Then be that the clear liquid of 5～50g/L pumps in the continuous ionic exchange system that anionite-exchange resin is housed and adsorbs with lactate concentration, it is assorted to be with concentration that the inorganic salt solution of pH2～10,0.001～0.2M is washed, and is that the acid solution of 0.1～2M carries out wash-out with concentration again; With nanofiltration ion-exchanging eluent is concentrated; At last with the molecular distillation means handle get final product high purity, high-quality L-lactic acid.
Wherein, described ultrafiltration apparatus use molecular weight cut-off is the ultra-filtration membrane of 5000～10000Dalton.
Wherein, described anionite-exchange resin is weak base anion-exchange resin.
It is wherein, described that to wash assorted inorganic salt solution be sodium-chlor, ammonium chloride or ammoniumsulphate soln.
Wherein, described wash-out acid solution is sulfuric acid or hydrochloric acid soln.
Wherein, described continuous ionic exchange system is the ion exchange system by the placed in-line operate continuously of 6～60 radical ion exchange columns, promptly by combined valve with the absorption in the ion exchange process, wash assorted, wash-out, regenerate and switch in order between four workshop sections, the adsorption stage ion exchange column is shifted out adsorption stage at once after resin absorption is saturated send into and wash assorted section and wash assorted, washing that to shift out at once behind assorted the end be that assorted section is sent into the wash-out section and carried out wash-out, shifting out the wash-out section after wash-out is finished at once sends into RS Regenerator Section and regenerates, shifting out RS Regenerator Section after regeneration is cleaned and to be finished at once sends into adsorption stage and adsorbs, so round-robin operating process, and the state of the 1st radical ion exchange column of two workshop sections switches and carries out synchronously, and guarantees to have at least a radical ion exchange column to be in absorption phase.Feed liquid enters from fixed bed top, finish the back in each operation and just the resin column of finishing operation " moved " and arrive next operation by the switching of valve, and the per pass operation by operating flow adjusting or the adjusting of resin loadings realizes synchronous operation.By controlling the flow velocity of each workshop section, can be so that keep same rhythm to carry out work from four workshop sections of the process of friendship.
Wherein, described nanofiltration use molecular weight cut-off is the nanofiltration membrane of 50～500Dalton.
Wherein, described molecular distillation equipment is a centrifugal molecular still, and service temperature is 40～60 ℃, and vacuum tightness is 0.1～100Pa.
Beneficial effect: the technology of separation and purification L-lactic acid of the present invention, improved the utilization ratio of resin, reduced resin demand and reached 40～60%, elutriant concentration uprises, wash assorted effectively, the consumption that has reduced eluent and washed assorted agent has reduced 30%～50% respectively; Consumption reduces more than 50% regenerators such as acid simultaneously, alkali owing to improved utilization ratio, has reduced the discharging of soda acid, and the yield of product has reached 90%.The present invention separates ultra-filtration membrane except that albumen technology, continuous ionic switching technology, nanofiltration concentrate, molecular distillation technique combines, make that separating and purifying technology of the present invention is simple and easy to do, effect is good, all unit operations all carry out under a lower temperature except that molecular distillation, the thermotolerance of product significantly improves, purity reaches more than 99%, and quality product has reached international most advanced level.
Embodiment:
Embodiment 1:
To pump into ultrafiltration apparatus to remove the macromolecular substance such as protein in the fermented liquid through pretreated lactic acid fermentation liquids (lactate concentration is 30g/L) such as centrifugal, decolourings, the molecular weight cut-off of ultra-filtration membrane is 10000Dalton.After clear liquid is diluted to 7g/L, regulate pH value to 2.5, pump in the continuous ionic exchange system that anionite-exchange resin 301 types are housed, adopt 18 radical ion exchange columns to constitute the continuous ionic exchange system, adsorption stage is 6, and washing assorted section is 3,3 of wash-out sections, RS Regenerator Section are 6.Every radical ion exchange column filling 100g weak anion resin, the absorption flow velocity is 15mL/min.Washing assorted liquid is the sodium chloride solution of pH2,0.05mol/L, and washing assorted flow velocity is 20mL/min.Elutriant is the hydrochloric acid soln of 0.5M, and elution flow rate is 10mL/min, and every 45min switches once from handing over post.Use the nanofiltration membrane of 100Dalton that wash-out is collected liquid and carry out desalination and concentration, utilizing molecular distillation technique again is 60 ℃ in temperature, and vacuum tightness is that the condition of 1Pa is carried out concentrating and separating, thus obtain purity up to 99%, the lactic acid of good heat resistance.
Embodiment 2:
To pump into ultrafiltration apparatus to remove the macromolecular substance such as protein in the fermented liquid through pretreated lactic acid fermentation liquids (lactate concentration is 100g/L) such as centrifugal, decolourings, the molecular weight cut-off of ultra-filtration membrane is 5000Dalton.After clear liquid is diluted to 50g/L, regulate pH value to 2.5, pump in the continuous ionic exchange system that anionite-exchange resin 302 types are housed, adopt 30 radical ion exchange columns to constitute the continuous ionic exchange system, adsorption stage is 10, and washing assorted section is 5,5 of wash-out sections, RS Regenerator Section are 10.Every radical ion exchange column filling 100g weak anion resin, the absorption flow velocity is 12mL/min.Washing assorted liquid is the sodium chloride solution of pH4,0.2mol/L, and washing assorted flow velocity is 10mL/min.Elutriant is the sulphuric acid soln of 0.1M, and elution flow rate is 5mL/min, and every 60min switches once from handing over post.Use the nanofiltration membrane of 50Dalton that wash-out is collected liquid and carry out desalination and concentration, utilizing molecular distillation technique again is 40 ℃ in temperature, and vacuum tightness is that the condition of 0.1Pa is carried out concentrating and separating, thus obtain purity up to 98%, the lactic acid of good heat resistance.
Embodiment 3:
To pump into ultrafiltration apparatus to remove the macromolecular substance such as protein in the fermented liquid through pretreated lactic acid fermentation liquids (lactate concentration is 20g/L) such as centrifugal, decolourings, the molecular weight cut-off of ultra-filtration membrane is 8000Dalton.After clear liquid is diluted to 5g/L, regulate pH value to 2.5, pump in the continuous ionic exchange system that anionite-exchange resin 311 types are housed, adopt 6 radical ion exchange columns to constitute the continuous ionic exchange system, adsorption stage is 2, and washing assorted section is 1,1 of wash-out section, RS Regenerator Section are 2.Every radical ion exchange column filling 100g weak anion resin, the absorption flow velocity is 10mL/min.Washing assorted liquid is the ammonium chloride solution of pH10,0.01mol/L, and washing assorted flow velocity is 8mL/min.Elutriant is the sulphuric acid soln of 2M, and elution flow rate is 4mL/min, and every 90min switches once from handing over post.Use the nanofiltration membrane of 500Dalton that wash-out is collected liquid and carry out desalination and concentration, utilizing molecular distillation technique again is 100 ℃ in temperature, and vacuum tightness is that the condition of 100Pa is carried out concentrating and separating, thus obtain purity up to 99%, the lactic acid of good heat resistance.
Embodiment 4:
To pump into ultrafiltration apparatus to remove the macromolecular substance such as protein in the fermented liquid through pretreated lactic acid fermentation liquids (lactate concentration is 30g/L) such as centrifugal, decolourings, the molecular weight cut-off of ultra-filtration membrane is 10000Dalton.After clear liquid is diluted to 20g/L, regulate pH value to 2.5, pump in the continuous ionic exchange system that anionite-exchange resin 313 types are housed, adopt 60 radical ion exchange columns to constitute the continuous ionic exchange system, adsorption stage is 20, and washing assorted section is 15,10 of wash-out sections, RS Regenerator Section are 15.Every radical ion exchange column filling 100g weak anion resin, the absorption flow velocity is 10mL/min.Washing assorted liquid is the ammoniumsulphate soln of pH7,0.1mol/L, and washing assorted flow velocity is 12mL/min.Elutriant is the hydrochloric acid soln of 1M, and elution flow rate is 7mL/min, and every 60min switches once from handing over post.Use the nanofiltration membrane of 200Dalton that wash-out is collected liquid and carry out desalination and concentration, utilizing molecular distillation technique again is 80 ℃ in temperature, and vacuum tightness is that the condition of 50Pa is carried out concentrating and separating, thus obtain purity up to 99%, the lactic acid of good heat resistance.
Claims (8)
1, a kind of novel process of separation and purification L-lactic acid is characterized in that: will pump into ultrafiltration apparatus through L-lactic acid fermentation liquid centrifugal, decolouring and remove Deproteinization; Then be that the clear liquid of 5～50g/L pumps in the continuous ionic exchange system that anionite-exchange resin is housed and adsorbs with lactate concentration, it is assorted to be with concentration that the inorganic salt solution of pH2～10,0.001～0.2M is washed, and is that the acid solution of 0.1～2M carries out wash-out with concentration again; With nanofiltration ion-exchanging eluent is concentrated; At last with the molecular distillation means handle get final product high purity, high-quality L-lactic acid.
2, the novel process of separation and purification L-lactic acid according to claim 1 is characterized in that it is the ultra-filtration membrane of 5000～10000Dalton that described ultrafiltration apparatus uses molecular weight cut-off.
3, the novel process of separation and purification L-lactic acid according to claim 1 is characterized in that described anionite-exchange resin is weak base anion-exchange resin.
4, the novel process of separation and purification L-lactic acid according to claim 1 is characterized in that described to wash assorted inorganic salt solution be sodium-chlor, ammonium chloride or ammoniumsulphate soln.
5, the novel process of separation and purification L-lactic acid according to claim 1 is characterized in that described wash-out acid solution is sulfuric acid or hydrochloric acid soln.
6, the novel process of separation and purification L-lactic acid according to claim 1, it is characterized in that described continuous ionic exchange system is the ion exchange system by the placed in-line operate continuously of 6～60 radical ion exchange columns, promptly by combined valve with the absorption in the ion exchange process, wash assorted, wash-out, regenerate and switch in order between four workshop sections, the adsorption stage ion exchange column is shifted out adsorption stage at once after resin absorption is saturated send into and wash assorted section and wash assorted, washing that to shift out at once behind assorted the end be that assorted section is sent into the wash-out section and carried out wash-out, shifting out the wash-out section after wash-out is finished at once sends into RS Regenerator Section and regenerates, shifting out RS Regenerator Section after regeneration is cleaned and to be finished at once sends into adsorption stage and adsorbs, so round-robin operating process, and the state of the 1st radical ion exchange column of two workshop sections switches and carries out synchronously, and guarantees to have at least a radical ion exchange column to be in absorption phase.
7, the novel process of separation and purification L-lactic acid according to claim 1 is characterized in that it is the nanofiltration membrane of 50～500Dalton that described nanofiltration uses molecular weight cut-off.
8, the novel process of separation and purification L-lactic acid according to claim 1 is characterized in that described molecular distillation equipment is a centrifugal molecular still, and service temperature is 40～60 ℃, and vacuum tightness is 0.1～100Pa.
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Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2010051676A1 (en) * | 2008-11-10 | 2010-05-14 | 南京工业大学 | A cleaning process of producing lactic acid |
| CN101851643A (en) * | 2010-06-23 | 2010-10-06 | 河南金丹乳酸科技有限公司 | Production equipment of crystalline L-lactic acid and method of producing crystalline L-lactic acid with production equipment |
| CN102190576A (en) * | 2010-03-08 | 2011-09-21 | 盐城海嘉诺生物工程有限公司 | Ion exchange liquid desugarization process for L-lactic acid |
| CN103724183A (en) * | 2013-12-16 | 2014-04-16 | 河南金丹乳酸科技股份有限公司 | Method of industrial production of lactic acid by employing molecular distillation technology |
| CN104910006A (en) * | 2015-04-21 | 2015-09-16 | 山东福瑞达生物科技有限公司 | Method for extracting lactic acid in Nisin fermentation waste liquid by using weakly basic anion exchange resin |
| CN105646193A (en) * | 2014-12-05 | 2016-06-08 | 中国石油化工股份有限公司 | Method used for separating and extracting lactic acid from fermentation broth |
| CN106431895A (en) * | 2016-09-18 | 2017-02-22 | 宁波工程学院 | Method for extracting lactic acid from fermentation liquor through combination of molecular distillation and extraction |
| CN107382713A (en) * | 2017-08-30 | 2017-11-24 | 沈阳金博地生态环保科技有限公司 | A kind of technique of purification of lactic acid |
| CN111574360A (en) * | 2020-05-25 | 2020-08-25 | 中粮营养健康研究院有限公司 | Method for separating lactic acid |
| CN111592458A (en) * | 2020-05-25 | 2020-08-28 | 中粮营养健康研究院有限公司 | Method for separating lactic acid |
| CN111777504A (en) * | 2020-08-11 | 2020-10-16 | 上海汉禾生物新材料科技有限公司 | Method for purifying L-lactic acid extracted from fermentation liquor |
| CN114699801A (en) * | 2021-09-08 | 2022-07-05 | 欧尚元(天津)有限公司 | Valve array type continuous ion exchange system for purification of red lactic acid |
| CN114702379A (en) * | 2021-09-08 | 2022-07-05 | 欧尚元(天津)有限公司 | Purification method of red lactic acid |
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2008
- 2008-03-04 CN CNA2008100203975A patent/CN101234962A/en active Pending
Cited By (21)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8545685B2 (en) | 2008-11-10 | 2013-10-01 | Nanjing University Of Technology | Cleaning process of producing lactic acid |
| WO2010051676A1 (en) * | 2008-11-10 | 2010-05-14 | 南京工业大学 | A cleaning process of producing lactic acid |
| CN102190576A (en) * | 2010-03-08 | 2011-09-21 | 盐城海嘉诺生物工程有限公司 | Ion exchange liquid desugarization process for L-lactic acid |
| CN101851643A (en) * | 2010-06-23 | 2010-10-06 | 河南金丹乳酸科技有限公司 | Production equipment of crystalline L-lactic acid and method of producing crystalline L-lactic acid with production equipment |
| CN101851643B (en) * | 2010-06-23 | 2013-05-22 | 河南金丹乳酸科技股份有限公司 | Production equipment of crystalline L-lactic acid and method of producing crystalline L-lactic acid with production equipment |
| CN103724183A (en) * | 2013-12-16 | 2014-04-16 | 河南金丹乳酸科技股份有限公司 | Method of industrial production of lactic acid by employing molecular distillation technology |
| CN103724183B (en) * | 2013-12-16 | 2015-10-28 | 河南金丹乳酸科技股份有限公司 | Utilize the method for molecular distillation technique industrial production of lactic acid |
| CN105646193A (en) * | 2014-12-05 | 2016-06-08 | 中国石油化工股份有限公司 | Method used for separating and extracting lactic acid from fermentation broth |
| CN105646193B (en) * | 2014-12-05 | 2018-04-10 | 中国石油化工股份有限公司 | A kind of method of the separation and Extraction lactic acid from zymotic fluid |
| CN104910006A (en) * | 2015-04-21 | 2015-09-16 | 山东福瑞达生物科技有限公司 | Method for extracting lactic acid in Nisin fermentation waste liquid by using weakly basic anion exchange resin |
| CN106431895B (en) * | 2016-09-18 | 2018-06-05 | 宁波工程学院 | Molecular distillation combines extraction for the method for extracting Lactic Acid from Fermentation Broth |
| CN106431895A (en) * | 2016-09-18 | 2017-02-22 | 宁波工程学院 | Method for extracting lactic acid from fermentation liquor through combination of molecular distillation and extraction |
| CN107382713A (en) * | 2017-08-30 | 2017-11-24 | 沈阳金博地生态环保科技有限公司 | A kind of technique of purification of lactic acid |
| CN111574360A (en) * | 2020-05-25 | 2020-08-25 | 中粮营养健康研究院有限公司 | Method for separating lactic acid |
| CN111592458A (en) * | 2020-05-25 | 2020-08-28 | 中粮营养健康研究院有限公司 | Method for separating lactic acid |
| CN111592458B (en) * | 2020-05-25 | 2022-12-23 | 中粮营养健康研究院有限公司 | Method for separating lactic acid |
| CN111777504A (en) * | 2020-08-11 | 2020-10-16 | 上海汉禾生物新材料科技有限公司 | Method for purifying L-lactic acid extracted from fermentation liquor |
| CN111777504B (en) * | 2020-08-11 | 2021-03-19 | 上海汉禾生物新材料科技有限公司 | Method for purifying L-lactic acid extracted from fermentation liquor |
| CN114699801A (en) * | 2021-09-08 | 2022-07-05 | 欧尚元(天津)有限公司 | Valve array type continuous ion exchange system for purification of red lactic acid |
| CN114702379A (en) * | 2021-09-08 | 2022-07-05 | 欧尚元(天津)有限公司 | Purification method of red lactic acid |
| CN114702379B (en) * | 2021-09-08 | 2022-09-20 | 欧尚元(天津)有限公司 | Purification method of red lactic acid |
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