CN102432610B - Folic acid production method for controlling content of technical pteroic acid - Google Patents
Folic acid production method for controlling content of technical pteroic acid Download PDFInfo
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Abstract
The invention provides a folic acid production method for controlling the content of technical pteroic acid and is characterized in that the folic acid production method comprises the following processing steps of: a crude product production step of using an intermediate for the folic acid production to prepare a folic acid crude product; an acid dissolution step of dissolving the folic acid crude product in an acid dissolution elutriation container by using a dilute sulfuric acid solution with the concentration of 25%-35% and carrying out elutriation and press filtration on the dissolved folic acid crude product to obtain an acid extract; an alkali dissolution and refining step of carrying out alkali dissolution on the acid extract by using alkali lye to obtain an alkali dissolution filtrate and refining the alkali dissolution filtrate for salt formation by using dilute acid so as to obtain the folic acid finished product. By reducing the concentration of dilute sulfuric acid, folic acid (the content of impurity technical pteroic acid is less than or equal to 0.6%) which accords with the requirement of European pharmacopeia is produced, and the production cost of folic acid is reduced.
Description
Technical field
The present invention relates to a kind of Acidum folicum production method, particularly relate to a kind of Acidum folicum production method of in the folic acid production process, controlling pteroic acid content in the folic acid finished product.
Background technology
Folic acid (C
19H
19N
7O
6) belong to the basic kind of VITAMIN, be anti-anemic, be applied to fields such as feed medicine and food.Folic acid generally is a kind of greenish orange yellow crystal or thin slice, and about 250 ℃ of carbonization deepenings are soluble in ethanol, alkali carbonate solution etc.
So folic acid is abundant name with content in the plant greenery.It is the abundantest to contain folic acid with liver in animal tissues.Originally be from liver, to extract, many now employing synthesis method productions (the Chinese invention patent application, the notification number that are respectively CN101973995A with reference to publication number are the Chinese invention patent of CN101182323B, CN101323614B), and have scientist attempting utilizing bacterium to produce the method (publication number is the Chinese invention patent application of CN1149626A) of folic acid.
As follows as the existing synthesis method general step of producing folic acid:
(1) produces preparation folic acid crude product production intermediate product, as this intermediate product, difference according to manufacturer, sometimes this intermediate product is different, use N-NSC 71042 and 2 such as the factory that has, 4,5-triamino-two kinds of intermediate products of 6-hydroxy pyrimidine vitriol prepare folic acid crude product (this method is a prior synthesizing method), and the producer that has utilizes para-amino benzoic acid, 2,4,5-triamino-6-hydroxy pyrimidine vitriol and trichloroacetone are produced folic acid crude product (Anhui a company is using), the producer that also has uses the N-NSC 71042,2,4,5-triamino-6-hydroxy pyrimidine vitriol and trichloroacetone are produced the folic acid crude product.
(2), crude product production: utilize above-mentioned folic acid production in the crude product retort, to react, after press filtration, obtain crude product with intermediate product;
(3), sour molten technology: in the molten elutriation jar of acid, use the acid fluid dissolves crude product, the crude product after the dissolving is obtained acid through elutriation, press filtration carry thing;
(4), molten, the process for refining of alkali:
The molten step of alkali: in the molten retort of alkali thing is carried in acid and added the water stirring, to 9.0-9.5, press filtration obtains alkali lixiviation liquid at the 90-100 ℃ of pH value of regulating with alkali lye;
Purification step: clarifying alkali lixiviation liquid enters and is refined into salt pan, 98 ± 2 ℃, regulate with dilute hydrochloric acid and to be refined into that material liquid PH value is 3.0-3.5 in the salt pan; Feed liquid is cooled to 55 ± 2 ℃, and material is separated out; Material is washed to PH=6～7, centrifugally gets rid of filter, dried material gets product then.
Wherein, in the molten process of above-mentioned acid, useful hydrochloric acid carries out sour molten technology, be 2010231213.8 Chinese invention patent application such as application number, and also useful sulfuric acid carries out sour molten technology, is 200810055491.4 Chinese invention patent application such as application number.Adopt sulfuric acid to compare, find that reaction effect is better with adopting hydrochloric acid, and can reduce production costs (unit consumption that the vitriolic unit consumption is lower than hydrochloric acid).
The folic acid finished product is when entering European Union market, and European Pharmacopoeia has the specification of quality of a strictness, i.e. content≤0.6% of impurity pteroic acid in the folic acid finished product.And the folic acid of present above-mentioned produced in conventional processes, especially by adopting sulfuric acid to carry out in the folic acid finished product that the molten technology of acid obtains, often the content aspect of impurity pteroic acid does not meet this requirement in the folic acid finished product, and since the structure of folic acid by pteroic acid (pteroic acid) and L-glutamic acid in conjunction with formation, though folic acid and pteroic acid have certain difference on molecular structure, but because the physico-chemical property of these two kinds of materials is similar, so the pteroic acid that wants to remove in the folic acid is very difficult, need to reduce its content in folic acid through repeatedly refining, can make the folic acid yield reduce greatly but repeatedly make with extra care, correspondingly cause the production cost of folic acid to improve greatly.
Summary of the invention
In order to reduce the content of pteroic acid in the finished product folic acid, we have carried out deep research to the whole production technology of folic acid, find that a part occurs in the crude product preparation process at the contained pteroic acid of folic acid finished product, but be a part seldom, and most pteroic acid is to occur when acid is molten.
According to this understanding, the technology that we will control pteroic acid content has focused in the research to the molten process of acid, the place of pinpointing the problems finally, it is exactly the excessive concentration of dilute sulphuric acid in the molten elutriation process of crude acid, cause a part of folic acid to be oxidized to pteroic acid, we reduce the concentration of dilute sulphuric acid under the situation that guarantees quality product and yield for this reason, produce the folic acid (content of impurity pteroic acid≤0.6%) that meets the European Pharmacopoeia requirement finally.
Be that the present invention is in order to realize reducing the content of pteroic acid in the finished product folic acid, a kind of Acidum folicum production method of controlling pteroic acid content is provided, and this Acidum folicum production method comprises following processing step: the crude product production stage: utilize the intermediate product of folic acid production usefulness to produce the folic acid crude product; The molten step of acid: in the molten elutriation container of acid,, the described folic acid crude product after the dissolving is obtained acid through elutriation, press filtration carry thing with the described folic acid crude product of acid fluid dissolves that utilizes the dilute sulphuric acid of concentration between 25%～35%; , purification step molten: utilize alkali lye that thing is carried in described acid and carry out alkali and moltenly obtain alkali lixiviation liquid, utilize diluted acid that described alkali lixiviation liquid is made with extra care to obtain the folic acid finished product with alkali.
In above-mentioned Acidum folicum production method, preferred: the acid concentration of described dilute sulphuric acid is more than 28%, more preferably: the acid concentration of described dilute sulphuric acid is below 32%, most preferably: the acid concentration of described dilute sulphuric acid is 30%.
In above-mentioned Acidum folicum production method, preferred: in the molten step of described acid, with the kilogram be measure unit described folic acid crude product quality and with the amount ratio of the described dilute sulphuric acid that is upgraded to measure unit between 1: 1.5～1: 2.1, more preferably this ratio is 1: 1.8.
In above-mentioned Acidum folicum production method, preferably: the intermediate product of described folic acid production usefulness comprises N-NSC 71042,2,4,5-triamino-6-hydroxy pyrimidine vitriol, para-amino benzoic acid, trichloroacetone are selected in the described intermediate product two kinds or two or more for use when producing described folic acid crude product.
In above-mentioned Acidum folicum production method, preferred: described alkali is molten, purification step comprises following two steps:
The molten step of alkali: acid carried thing in the molten reaction vessel of alkali and add water and stir and obtain the mixture that thing and described water are carried in described acid, under the certain temperature condition, regulate the pH value of described mixture with alkali lye, press filtration obtains alkali lixiviation liquid; Purification step: clarifying described alkali lixiviation liquid is added refining salify container, under the certain temperature condition, regulate the pH value salify of described alkali lixiviation liquid with dilute hydrochloric acid or CP hydrochloric acid; Material is separated out in the described refining salify container; With described material cooling and suction filtration oven dry, promptly get the folic acid finished product.
In above-mentioned Acidum folicum production method, preferably in the molten step of described alkali: with alkali lye the pH value of described mixture is adjusted to 9.0～9.5 when heating described mixture and reaching 90～102 ℃, press filtration obtains alkali lixiviation liquid; In described purification step: regulate when described alkali lixiviation liquid temp reaches 95～100 ℃, with CP hydrochloric acid that material liquid PH value is 3.0～3.5 in the described refining salify container; Feed liquid is cooled to below 57 ℃, and material is separated out; Material is washed to PH=6～7, centrifugally gets rid of filter, dried material promptly gets the folic acid finished product then.
In above-mentioned Acidum folicum production method, preferably in the molten step of described alkali, described mixture is to obtain by described acid being carried in the water that thing is added to 60～80 ℃, and, when being heated to 98～102 ℃, the temperature of described mixture regulates pH value to 9.0～9.5 of described mixture with alkali lye, the liquid caustic soda content of described alkali lye is more than or equal to 30%, in described purification step: regulate when described alkali lixiviation liquid temp reaches 98 ± 2 ℃, with CP hydrochloric acid that material liquid PH value is 3.0～3.5 in the described refining salify container.
Embodiment
In order to reduce the content of pteroic acid in the finished product folic acid, we have carried out deep research to the whole production technology of folic acid, find that a part occurs in the crude product preparation process at the contained pteroic acid of folic acid finished product, but be a part seldom, and most pteroic acid is to occur when acid is molten.
According to this understanding, the technology that we will control pteroic acid content has focused in the research to crude product production and sour molten process, especially sour molten process.The place of pinpointing the problems finally, be exactly the excessive concentration of dilute sulphuric acid in the molten elutriation process of crude acid, cause a part of folic acid to be oxidized to pteroic acid, because the vitriolic oxidation capacity is associated with its acid concentration, generally speaking, acid concentration is high more, and oxidation capacity is strong more, and acid concentration is low more, oxidation capacity is weak more, based on this understanding, in order to reduce the possibility that folic acid is oxidized to pteroic acid, the present inventor thinks the concentration that should attempt reducing the dilute sulphuric acid that uses in the sour molten technology.
Based on this understanding, we are reduced to 30% (mass content) to the concentration of dilute sulphuric acid by 45% under the situation that guarantees quality product and yield for this reason, produce the folic acid (content of impurity pteroic acid≤0.6%) that meets the European Pharmacopoeia requirement finally.
Based on the above-mentioned achievement of discovering, for the pteroic acid content of controlling in the folic acid makes its requirement that reaches European Pharmacopoeia, the present inventor improves existing technology, specifically, is the sour molten technology of having improved in the existing technology.Integral body is discussed below.
As the intermediate product of producing preparation folic acid crude product, just as described in the background section, manufacturer's difference, this intermediate product is different.Though below argumentation with wherein a kind of be that example describes; do not use illustrative intermediate product to prepare the folic acid crude product but do not represent the claimed Acidum folicum production method of the present invention only to be applicable to; so long as those skilled in the art can expect in conjunction with prior art, all in protection scope of the present invention.Below for example also identical to each technology.
(1), crude product production: utilize NSC 71042,2,4,5-triamino-6-hydroxy pyrimidine vitriol and trichloroacetone are produced the folic acid crude product and are reacted in the crude product retort, obtain crude product after press filtration; The waste liquid that generates after the press filtration adsorption treatment of decolouring can be used for follow-up recycle.
(2), sour molten technology: in the molten elutriation of acid is irritated,, the crude product after the dissolving is obtained acid through elutriation, press filtration carry thing with the acid fluid dissolves crude product of dilute sulphuric acid.
In this sour molten technology, the acid concentration of used dilute sulphuric acid (mass content) requires below 35%, and more than 25%, more preferably between 28～32%, its purpose is exactly in order to reduce the oxidation capacity of acid solution to the folic acid crude product.
In the above-mentioned technology, why acid concentration being limited between 25%～35%, is because if acid concentration is higher than 35%, and the folic acid amount that then is oxidized to pteroic acid will increase, and causes pteroic acid amount contained in the folic acid finished product to increase, and does not meet the survey requirement of European Pharmacopoeia; And if sulfuric acid concentration is lower than 25%, then can't finishes dissolving folic acid crude product and then elutriation and obtain the function that thing is carried in acid.
As the dilution heat of sulfuric acid of the above-mentioned concentration requirement of in the molten technology of acid, using, can before the molten technology of acid, be ready to.Both can be with vitriol oil compound concentration at about 30% dilute sulphuric acid especially between 25%～35%, also can use at the concentration of selling on market dilute sulphuric acid of 30% especially between 25%～35%.
Concrete operations when utilizing the vitriol oil to prepare satisfactory dilute sulphuric acid are exemplified as: the 250L vitriol oil (mass concentration is more than or equal to 92.5%) is pumped into vitriol oil high level tank, the water that in the dilute sulphuric acid preparing tank, adds 1000L, start and stir, the vitriol oil slowly added open jacket water (J.W.) cooling in the dilute sulphuric acid preparing tank simultaneously, preparation finishes the dilute sulphuric acid (mass concentration is 30%) that will prepare with standby in the high-order test tank of vacuum suction dilute sulphuric acid.
Concrete sour molten technology is: the wet crude product 700-900KG that input has been got ready in the molten jar of acid, then folic acid crude product and dilute sulphuric acid are slowly added calculated dilute sulphuric acid according to the mode of proportion relation between the quality (unit K g) of folic acid crude product and the vitriolic volume (unit liter), add acid and begin to stir, complete molten and do not have block and occur until crude product.
As for this ratio, in actual production process, it is fixed to come according to client's demand (being generally other requirements outside the pteroic acid content).The client need sometimes USP23 for example (meeting American Pharmacopeia 23 editions), needs USP32 sometimes, what also have wants EP's (European Pharmacopoeia), production technique and lab work also need to carry out inching according to client's demand, such as the folic acid of producing different quality demands with different dilute sulphuric acid additional proportions.From the angle of further reduction pteroic acid content, preferably this ratio is generally between 1: 1.5～1: 2.1, especially preferably about 1: 1.8.
(3), the molten technology of alkali: in the molten retort of alkali, add tap water 2000L, open stirring, open the molten jar jacket steam valve of alkali and heat, temperature reaches 60～80 ℃ in jar, is more preferably to add 80～100KG acid carry thing when 70 ℃ of left and right sides, continue to be heated to 90～102 ℃, be more preferably 98～102 ℃, regulate pH value to 9.0～9.5, be incubated 1 hour with alkali lye (alkali lye of preferred liquid caustic soda content 〉=30%), add activated carbon decolorizing, the decolouring press filtration that finishes obtains alkali lixiviation liquid.
(4), process for refining: clarifying alkali lixiviation liquid enters treatment tank, open then and stir and the jacket steam valve, alkali lye is heated to 95 ℃～100 ℃ temperature range, such as 98 ± 2 ℃, regulating the interior material liquid PH value of treatment tank with diluted acid (preferably such as dilute hydrochloric acid (technical hydrochloric acid) or CP hydrochloric acid) is 3.0～3.5; Feed liquid is cooled to 55 ± 2 ℃ in other words below 57 ℃, is more preferably below 55 ℃, material is separated out; After treating that material is separated out, material is put into the quiet filter in quiet filter tank, after the absence of liquid of quiet filter tank, add an amount of purified water and wash, centrifugally get rid of filter to PH=6～7, dried material then, (folic acid wet product) gets product.
The above-mentioned CP hydrochloric acid of mentioning is a kind of analytical pure hydrochloric acid, outward appearance is the liquid that water white transparency has pungent odour, mass content is at 36-38% (g/g), require molysite≤0.0001%, heavy metal≤0.002%, and dilute hydrochloric acid is exactly so-called technical hydrochloric acid, outward appearance is colourless or yellow transparent has the liquid of pungent odour, mass content is 〉=31%, impurity is not wherein required, consider that this operation is a refining step, and use CP hydrochloric acid more to be difficult for bringing into other impurity, so in above-mentioned process for refining, more preferably use CP hydrochloric acid.
Through being tested, learns the folic acid finished product of producing thus, the content of the impurity pteroic acid in the finished product folic acid that obtains by above-mentioned technology is 0.5%, carry out the content of impurity pteroic acid among the molten preparation method who produces folic acid of acid compares 1.0～1.5% with the dilute sulphuric acid of traditional use higher concentration, the content of impurity pteroic acid reduces greatly, has satisfied the requirement of European Pharmacopoeia; And the product yield of folic acid is compared with traditional technology, the dilute sulphuric acid of traditional use higher concentration carries out the molten preparation method's who produces folic acid of acid folic acid yield between 52.5～53.5%, and the present invention replace to the lower dilute sulphuric acid of concentration after the folic acid yield between 53-53.5%, in view of this, though the folic acid yield does not improve greatly, at least obviously do not reduce yet.
The invention effect
Carry out the sour molten technology of folic acid crude product by the dilute sulphuric acid that adopts lower concentration, reduced the possibility that folic acid is oxidized to pteroic acid, reduced the content of pteroic acid in the finished product folic acid, make product can meet the strict demand of European Pharmacopoeia, squeeze into the European market for the folic acid product and lay a solid foundation, simultaneously because the reduction of the acid concentration of the dilute sulphuric acid that uses has also reduced the vitriolic unit consumption, reduce the cost of product, strengthened competitiveness of product.
Claims (5)
1. an Acidum folicum production method of controlling pteroic acid content is characterized in that, this Acidum folicum production method comprises following processing step:
The crude product production stage: utilize the intermediate product NSC 71042,2,4 of folic acid production usefulness, 5-triamino-6-hydroxy pyrimidine vitriol and trichloroacetone react in the crude product retort, obtain the folic acid crude product after press filtration;
The molten step of acid: the described folic acid crude product of acid fluid dissolves that in the molten elutriation container of acid, utilizes the dilute sulphuric acid of concentration between 25%～35%, wherein be with the kilogram measure unit described folic acid crude product quality and with the amount ratio of the described dilute sulphuric acid that is upgraded to measure unit between 1:1.5 ~ 1:2.1, the described folic acid crude product after the dissolving is obtained acid through elutriation, press filtration carries thing; With
Molten, the purification step of alkali: utilize alkali lye that thing is carried in described acid and carry out the molten alkali lixiviation liquid that obtains of alkali, specific as follows: as in the molten retort of alkali, to add tap water 2000L, open stirring, opening molten jar of jacket steam valve of alkali heats, when temperature in the jar reaches 60～80 ℃, add the described acid of 80～100KG and carry thing, continue to be heated to 90～102 ℃, regulate pH value to 9.0～9.5 with alkali lye, be incubated 1 hour, press filtration obtains alkali lixiviation liquid behind the adding activated carbon decolorizing; Utilize diluted acid that described alkali lixiviation liquid is made with extra care and obtain the folic acid finished product, specific as follows: that clarifying alkali lixiviation liquid is placed treatment tank, open then and stir and the jacket steam valve, alkali lixiviation liquid is heated to 95 ℃ ~ 100 ℃ temperature range, the pH value of regulating feed liquid in the treatment tank with dilute hydrochloric acid or CP hydrochloric acid is 3.0～3.5, feed liquid is cooled to below 55 ± 2 ℃ then, after treating that material is separated out, material is put into the quiet filter in quiet filter tank, after the absence of liquid of quiet filter tank, add an amount of purified water with material wash to PH be 6～7, centrifugally then get rid of filter, dried material obtains the folic acid finished product.
2. the Acidum folicum production method of control pteroic acid content as claimed in claim 1 is characterized in that the acid concentration of described dilute sulphuric acid is more than 28%.
3. the Acidum folicum production method of control pteroic acid content as claimed in claim 2 is characterized in that the acid concentration of described dilute sulphuric acid is below 32%.
4. the Acidum folicum production method of control pteroic acid content as claimed in claim 3 is characterized in that, the acid concentration of described dilute sulphuric acid is 30%.
5. the Acidum folicum production method of control pteroic acid content as claimed in claim 1 is characterized in that, the amount ratio between described folic acid crude product and the described dilute sulphuric acid is 1:1.8.
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Families Citing this family (8)
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| CN103102351B (en) * | 2013-01-31 | 2015-03-04 | 宁波九胜创新医药科技有限公司 | Refining method for preparing high-purity folic acid |
| CN104098569B (en) * | 2014-08-02 | 2016-05-11 | 济南康和医药科技有限公司 | A kind of purification process of medicinal folic acid |
| CN106749257A (en) * | 2017-01-19 | 2017-05-31 | 辛纪衡 | The purification process of folic acid |
| CN107312004B (en) * | 2017-06-14 | 2019-07-19 | 河北冀衡（集团）药业有限公司 | A kind of production method of folic acid |
| CN109232574B (en) * | 2017-07-11 | 2021-04-09 | 北京斯利安药业有限公司 | Effective folic acid purification method |
| CN107365311B (en) * | 2017-08-16 | 2020-04-21 | 浙江圣达生物药业股份有限公司 | Preparation method and application of trans-folic acid |
| CN108084185A (en) * | 2017-12-29 | 2018-05-29 | 常州市新鸿医药化工技术有限公司 | A kind of environment-friendly type folic acid process for purification |
| CN109265460B (en) * | 2018-12-04 | 2020-08-11 | 北京斯利安药业有限公司 | Purification method of folic acid |
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