阅读说明：本技术 一种d-泛酸钙制备新工艺 (Novel process for preparing D-calcium pantothenate ) 是由 吴江 于 2020-05-14 设计创作，主要内容包括：一种D-泛酸钙制备新工艺本发明涉及一种D-泛酸钙制备新工艺。本发明基本方案是：将DL-泛解酸内酯配成含量为16-26%的水溶液,加入此水溶液质量的5-15%生物酶,搅拌均匀后,在23-30℃缓慢滴加此水溶液所含D-泛解酸内酯0.49-0.51倍摩尔量的β-氨基丙酸钙含量为20%-30%的水溶液。一直反应至D-泛解酸内酯水解完全过滤出清液,滤饼生物酶循环使用。滴加过程中保持反应体系PH值为6.0-7.3之间。反应完成后清液在真空高于-0.085MPa浓缩至115-120℃,降温到65℃以下加入重量0.5-0.8倍D-泛解酸β-氨基丙酸钙的甲醇,搅拌降温到20-40℃,过滤,滤饼用甲醇洗涤、打浆、再洗涤实现纯化,几次滤液汇集起来,回收甲醇后消旋成DL-泛解酸内酯再次使用。滤饼通过105-125℃和150-160℃两级温区干燥后,降温出料即得D-泛酸钙。本发明在拆分反应的同时,一步生成D-泛酸钙的前体物质D-泛解酸β-氨基丙酸钙。避开了萃取分离D-泛解酸内酯的过程。(The invention relates to a novel process for preparing D-calcium pantothenate. The basic scheme of the invention is as follows: preparing the DL-pantoic acid lactone into an aqueous solution with the content of 16-26 percent, adding 5-15 percent of biological enzyme by mass of the aqueous solution, stirring uniformly, and slowly dropwise adding an aqueous solution with the content of 20-30 percent of beta-calcium aminopropionate with the molar weight of 0.49-0.51 time that of the D-pantoic acid lactone in the aqueous solution at 23-30 ℃. Reacting until D-pantoic acid lactone is hydrolyzed completely, filtering to obtain clear liquid, and recycling the biological enzyme in filter cakes. The PH value of the reaction system is kept between 6.0 and 7.3 in the dropping process. After the reaction is finished, concentrating the clear liquid to 115-120 ℃ under the vacuum pressure higher than-0.085 MPa, cooling to below 65 ℃, adding methanol with the weight 0.5-0.8 time that of D-pantoic acid beta-amino calcium propionate, stirring, cooling to 20-40 ℃, filtering, washing a filter cake with methanol, pulping, washing again to realize purification, collecting the filtrates for several times, and racemizing the filtrate into DL-pantoic acid lactone for reuse after recovering the methanol. Drying the filter cake in two temperature regions of 105-125 ℃ and 150-160 ℃, cooling and discharging to obtain the D-calcium pantothenate. The method can generate a precursor substance of D-calcium pantothenate, namely D-calcium pantoate beta-aminopropionate in one step during the resolution reaction. Avoids the process of extracting and separating D-pantoic acid lactone.)

1. A new process for preparing D-calcium pantothenate comprises the following steps:

(1) preparing a splitting system: adding 6000 and 10000 kilograms of tap water into a 15m ethanol cultivation reaction kettle, adding 1600 and 2600 kilograms of DL-pantoic acid lactone to prepare a 16-26 percent DL-pantoic acid lactone aqueous solution, adding 5-15 percent of biological enzyme by mass of the aqueous solution, and stirring for 0.5-2 hours at 23-30 ℃ for later use;

(2) and dropwise adding an aqueous solution of beta-calcium aminopropionate: slowly dripping an aqueous solution containing 20-30% of beta-calcium aminopropionate in an amount which is 0.49-0.51 times of the molar amount of D-pantolactone in the step (1) under the stirring condition at 23-30 ℃, keeping the pH value of a reaction system between 6.0 and 7.3 in the dripping process, reacting until D-ester is completely hydrolyzed, filtering to obtain a clear liquid, and recycling a filter cake biological enzyme (sampling the filtered clear liquid, wherein the clear liquid takes the end point that the specific optical rotation at 23-30 ℃ converted from the L-pantolactone is more than or equal to 57 degrees in the clear liquid);

(3) and dehydrating and adding a solvent: after the reaction is finished, concentrating the clear solution to 115-120 ℃ under the vacuum pressure higher than-0.085 MPa, cooling to below 65 ℃, adding methanol with the weight 0.5-0.8 time that of D-pantoic acid beta-amino calcium propionate, stirring and cooling to 20-40 ℃;

(4) filtering, separating and purifying: filtering, washing the filter cake by using methanol with weight 0.5-0.8 time of that of the D-pantoic acid beta-amino calcium propionate for more than three times, taking out the filter cake, adding methanol with weight 0.5-0.8 time of that of the D-pantoic acid beta-amino calcium propionate, stirring and pulping, filtering again, adding methanol with weight 0.3-0.4 time of that of the D-pantoic acid beta-amino calcium propionate for more than one time, washing, collecting filtrates, recovering methanol, and racemizing into DL-pantoic acid lactone for reuse;

(5) d-calcium pantothenate formation: the filter cake enters a first-stage vibrating fluidized bed to be dried at the temperature of 105 ℃ and 125 ℃ until the water content is lower than 0.5 percent, then enters a second-stage vibrating fluidized bed to be dried for more than 1 hour at the temperature of 150 ℃ and 160 ℃, and then is cooled to the temperature below 40 ℃ by using a drying cold air fluidized bed, so that the obtained product is the D-calcium pantothenate.

2. The novel process for preparing calcium D-pantothenate according to claim 1, wherein: in the step (1), preparing a DL-pantolactone aqueous solution with the content of 16-26%, and adding 5-15% of biological enzyme by mass of the aqueous solution at 23-30 ℃.

3. The novel process for preparing calcium D-pantothenate according to claim 1, wherein: in the step (2), 0.49-0.51 times molar weight of beta-calcium aminopropionate aqueous solution of D-pantolactone contained in the step (1) is dripped, and the PH value of the reaction system is kept between 6.0 and 7.3 in the dripping process.

4. The novel process for preparing calcium D-pantothenate according to claim 1, wherein: in the step (2), the content of the beta-calcium aminopropionate in the beta-calcium aminopropionate aqueous solution is 20% -30%.

5. The novel process for preparing calcium D-pantothenate according to claim 1, wherein: in the step (2), the specific optical rotation at 23-30 ℃ converted from L-pantoic acid lactone is more than or equal to 57 degrees in the clear solution as an end point.

6. The novel process for preparing calcium D-pantothenate according to claim 1, wherein: in the step (3), the supernatant after the reaction is completed is concentrated to 115-120 ℃ under vacuum higher than-0.085 MPa.

7. The novel process for preparing calcium D-pantothenate according to claim 1, wherein: in the step (3), methanol with weight 0.5-0.8 time of that of the D-pantoic acid beta-calcium aminopropionate is added when the temperature is reduced to be below 65 ℃.

8. The novel process for preparing calcium D-pantothenate according to claim 1, wherein: in the step (4), the filter cake is washed by methanol with weight 0.5-0.8 time of that of the D-pantoic acid beta-calcium aminopropionate for more than three times, the filter cake is taken out, the methanol with weight 0.5-0.8 time of that of the D-pantoic acid beta-calcium aminopropionate is stirred and pulped, and then the filter cake is filtered, and the methanol with weight 0.3-0.4 time of that of the D-pantoic acid beta-calcium aminopropionate is washed by more than one time.

9. The novel process for preparing calcium D-pantothenate according to claim 1, wherein: in the step (5), drying is carried out at 105 ℃ and 125 ℃ until the moisture content is lower than 0.5 percent.

10. The novel process for preparing calcium D-pantothenate according to claim 1, wherein: in the step (5), drying is carried out at the temperature of 150-160 ℃ for more than 1 hour, and the temperature is reduced to be below 40 ℃.

Technical Field

The invention relates to a novel process for preparing D-calcium pantothenate.

Background

Calcium D-pantothenate is vitamin B5, chemically (R) - (+) -N- (2, 4-dihydroxy-3, 3-dimethyl-1-oxobutyl) - β -alanine calcium salt, english name: d- (+) -Pantothenic acid calcium salt as an important nutrient component is widely used in the fields of feed additives, food additives, medicines and the like;

the synthesis route of the D-calcium pantothenate adopts the method that beta-aminopropionic acid reacts with calcium oxide in methanol to synthesize the beta-calcium aminopropionate, D-pantoic acid lactone is added after the beta-calcium aminopropionate is filtered to synthesize the D-calcium pantothenate, the D-calcium pantothenate is separated out through low-temperature crystallization, and the mother liquor of the D-calcium pantothenate is recycled to recycle the raw materials of the methanol, the calcium, the D-pantoic acid lactone, the beta-aminopropionic acid and the like; the recycled or deteriorated materials are treated by an environment-friendly system as waste liquid, sulfuric acid and a large amount of organic solvents are utilized in the recycling process, the loss is increased, the operation environment is poor, the comprehensive utilization rate of main raw materials in the process can only reach 80-85% in industrial production, and D-pantolactone is obtained by separating from DL-pantolactone by using a separation reagent such as biological enzyme and the like and then performing a complex extraction process.

Disclosure of Invention

The invention takes DL-pantoic acid lactone, beta-aminopropionic acid and beta-aminopropionic acid calcium formed by hydration of calcium oxide as raw materials, biological enzyme as a catalyst and methanol as an auxiliary solvent to synthesize the D-calcium pantothenate, and the basic process comprises the following steps: preparing DL-pantoic acid lactone into 16-26% water solution, adding 5-15% biological enzyme of the water solution, stirring uniformly, slowly dripping 0.49-0.51 times molar amount of water solution containing beta-calcium amino propionate with 20-30% content in the water solution at 23-30 deg.C, reacting until D-pantoic acid lactone is hydrolyzed completely, filtering to obtain clear liquid, recycling filter cake biological enzyme (sampling the clear liquid, concentrating the clear liquid to 115-120 deg.C under vacuum higher than-0.085 MPa, cooling to 65 deg.C, adding 0.5-0.8 times weight of methanol of D-pantoic acid beta-calcium amino propionate), stirring and cooling to 20-40 ℃, filtering, washing the filter cake for more than three times by using methanol with weight 0.5-0.8 time of that of the D-pantoic acid beta-calcium amino propionate, taking out the filter cake, stirring and pulping by using methanol with weight 0.5-0.8 time of that of the D-pantoic acid beta-calcium amino propionate, filtering again, washing the methanol with weight 0.3-0.4 time of that of the D-pantoic acid beta-calcium amino propionate for more than one time, converging filtrate for several times, and racemizing the recovered methanol into DL-pantoic acid lactone for reuse; the filter cake enters the first-stage vibrating fluidized bed to be dried at the temperature of 105 ℃ and 125 ℃ until the moisture is lower than 0.5 percent, and then enters the second-stage vibrating fluidized bed to be dried for more than 1 hour at the temperature of 150 ℃ and 160 ℃. And then cooling to below 40 ℃ by using a dry cold air fluidized bed to obtain the product, namely the D-calcium pantothenate.

The technical scheme adopted for realizing the above purpose of the invention is as follows: a new process for preparing D-calcium pantothenate comprises the following steps:

(1) preparing a splitting system: adding 6000 and 10000 kilograms of tap water into a 15m ethanol cultivation reaction kettle, adding 1600 and 2600 kilograms of DL-pantoic acid lactone to prepare a 16-26 percent DL-pantoic acid lactone aqueous solution, adding 5-15 percent of biological enzyme by mass of the aqueous solution, and stirring for 0.5-2 hours at 23-30 ℃ for later use;

(2) and dropwise adding an aqueous solution of beta-calcium aminopropionate: slowly dripping an aqueous solution containing 20-30% of beta-calcium aminopropionate in an amount which is 0.49-0.51 times of the molar amount of D-pantolactone in the step (1) under the stirring condition at 23-30 ℃, keeping the pH value of a reaction system between 6.0 and 7.3 in the dripping process, reacting until D-ester is completely hydrolyzed, filtering to obtain a clear liquid, and recycling a filter cake biological enzyme (sampling the filtered clear liquid, wherein the clear liquid takes the end point that the specific optical rotation at 23-30 ℃ converted from the L-pantolactone is more than or equal to 57 degrees in the clear liquid);

(3) and dehydrating and adding a solvent: after the reaction is finished, concentrating the clear solution to 115-120 ℃ under the vacuum pressure higher than-0.085 MPa, cooling to below 65 ℃, adding methanol with the weight 0.5-0.8 time that of D-pantoic acid beta-amino calcium propionate, stirring and cooling to 20-40 ℃;

(4) filtering, separating and purifying: filtering, washing the filter cake by using methanol with weight 0.5-0.8 time of that of the D-pantoic acid beta-amino calcium propionate for more than three times, taking out the filter cake, adding methanol with weight 0.5-0.8 time of that of the D-pantoic acid beta-amino calcium propionate, stirring and pulping, filtering again, adding methanol with weight 0.3-0.4 time of that of the D-pantoic acid beta-amino calcium propionate for more than one time, washing, collecting filtrates, recovering methanol, and racemizing into DL-pantoic acid lactone for reuse;

(5) d-calcium pantothenate formation: the filter cake enters a first-stage vibrating fluidized bed to be dried at the temperature of 105 ℃ and 125 ℃ until the water content is lower than 0.5 percent, then enters a second-stage vibrating fluidized bed to be dried for more than 1 hour at the temperature of 150 ℃ and 160 ℃, and then is cooled to the temperature below 40 ℃ by using a drying cold air fluidized bed, so that the obtained product is the D-calcium pantothenate.

In the step (1), preparing a DL-pantolactone aqueous solution with the content of 16-26%, and adding 5-15% of biological enzyme by mass of the aqueous solution at 23-30 ℃.

In the step (2), 0.49-0.51 times molar weight of the beta-calcium aminopropionate aqueous solution of the D-pantolactone contained in the step (1) is added dropwise. The PH value of the reaction system is kept between 6.0 and 7.3 in the dropping process.

In the step (2), the content of the beta-calcium aminopropionate in the beta-calcium aminopropionate aqueous solution is 20% -30%.

In the step (2), the specific optical rotation at 23-30 ℃ converted from L-pantoic acid lactone is more than or equal to 57 degrees in the clear solution as an end point.

In the step (3), the supernatant after the reaction is completed is concentrated to 115-120 ℃ under vacuum higher than-0.085 MPa.

In the step (3), methanol with weight 0.5-0.8 time of that of the D-pantoic acid beta-calcium aminopropionate is added when the temperature is reduced to be below 65 ℃.

In the step (4), the filter cake is washed by methanol with weight 0.5-0.8 time of that of the D-pantoic acid beta-calcium aminopropionate for more than three times, the filter cake is taken out, the methanol with weight 0.5-0.8 time of that of the D-pantoic acid beta-calcium aminopropionate is stirred and pulped, and then the filter cake is filtered, and the methanol with weight 0.3-0.4 time of that of the D-pantoic acid beta-calcium aminopropionate is washed by more than one time.

In the step (5), drying is carried out at 105 ℃ and 125 ℃ until the moisture content is lower than 0.5 percent.

In the step (5), drying is carried out at the temperature of 150-160 ℃ for more than 1 hour, and the temperature is reduced to be below 40 ℃.

Therefore, compared with the prior art, the invention has the following advantages:

1. the method can generate a precursor substance of D-calcium pantothenate, namely D-calcium pantoate beta-aminopropionate in one step during the resolution reaction. The process of extracting and separating D-pantoic acid lactone is avoided, and the production flow is greatly shortened;

2. the process has no working procedure of extracting D-pantolactone, and the generation system does not use an extraction solvent, thereby ensuring the generation safety and the process stability;

3. compared with the prior art, the use amount of methanol in the process is reduced by more than 40 percent;

4. the process does not remove the residual methanol in the product of the D-calcium pantothenate by a rectification method;

5. the yield of the product of the process is more than 95 percent and even approaches 100 percent;

6. the process adopts water to synthesize beta-calcium aminopropionate and directly uses the filtered beta-calcium aminopropionate aqueous solution;

7. the process has no mother liquor recovery process.

The invention is further illustrated with reference to the following examples (the scope of protection includes, but is not limited to, the following examples).

Example 1

(1) Preparing a splitting system: 10000 kilograms of tap water is added into a 15m ethanol production kettle, 2600 kilograms (20 kilomoles) of pantolactone is added to prepare 20.63 percent of pantolactone aqueous solution, 1000 kilograms of biological enzyme is added, and the mixture is stirred for 0.5 hour at the temperature of 23-30 ℃ for standby application;

(2) and dropwise adding an aqueous solution of beta-calcium aminopropionate: slowly dripping 4154 kg (5 kmole) of beta-calcium aminopropionate aqueous solution with the content of 26% at the temperature of 23-30 ℃ under the stirring state, keeping the pH value of a reaction system between 6.8 and 7.3 in the dripping process, reacting for 23 hours, filtering out clear liquid, and detecting the specific optical rotation (converted by L-pantoic acid lactone) of the clear liquid at the temperature of 23 ℃ to be 57.1 degrees;

(3) and dehydrating and adding a solvent: after the reaction is finished, concentrating the clear liquid to 115 ℃ under the vacuum of more than-0.085 MPa, cooling to 65 ℃, adding 1280 kg of methanol, stirring and cooling to 20 ℃;

(4) filtering, separating and purifying: filtering, washing the filter cake with 1280 kg of methanol for more than three times, taking out the filter cake, adding 1280 kg of methanol, stirring and pulping, filtering again, adding 768 kg of methanol for more than one time of washing, collecting the filtrates, recovering methanol, racemizing to DL-pantoic acid lactone for reuse;

(5) d-calcium pantothenate formation: the filter cake enters a first-stage vibrating fluidized bed to be dried at the temperature of 105 ℃ and 125 ℃ until the water content is 0.5 percent, then enters a second-stage vibrating fluidized bed to be dried for 1 hour at the temperature of 150 ℃ and 160 ℃, and then is cooled to 40 ℃ by using a drying cold air fluidized bed, the obtained product is the D-calcium pantothenate, and the detected properties of the product meet the specification, the calcium content is 8.3 percent, the nitrogen content is 5.8 percent, the specific rotation is plus 26.3 percent^oLoss on drying of 1.3% and heavy metal less than 0.002% and 0.1% of methanol.