【作者】 曹晓伟；

【导师】 任保增；

【作者基本信息】 郑州大学 ， 化学工程， 2009， 硕士

【摘要】 维生素C聚磷酸酯及其镁盐既性质稳定,又能很好的发挥维生素C的作用,被广泛应用于饲料添加剂,食品营养添加剂,化妆品美白添加剂,医药辅助制剂等。随着生活水平的提高,维生素C聚磷酸酯及其镁盐有着更加巨大的需求空间。结合维生素C聚磷酸酯现有的直接酰化法工艺技术路线,本文改进了工艺条件,提高收率;针对维生素C磷酸酯镁现有的后处理工艺,本文提出了在酸性条件下水解脱除保护基的低能耗的处理工序。1.以维生素C为原料,三偏磷酸钠为磷酸化试剂,氯化钙为催化剂,在极性水溶液体系中发生酯化反应生成维生素C聚磷酸酯。通过单因素及正交实验,讨论了原料配比(维生素C与三偏磷酸钠),反应温度,催化剂用量和溶液pH值对产品维生素C聚磷酸酯收率的影响,获得了适宜的反应条件:反应温度为35℃,维生素C与三偏磷酸钠的摩尔配比为1:1.3,维生素C与氯化钙的摩尔配比为1:0.15,反应溶液pH为9,在该反应条件下,维生素C聚磷酸酯收率为76.58%。2.以维生素C为原料,采用基团保护法,先用丙酮对维生素C的5、6位羟基进行保护生成中间产物5,6-O-异丙叉维生素C,再以三氯氧磷为磷酸化试剂,吡啶为催化剂,在碱性条件下发生磷酰化反应,后在酸性条件下水解脱除保护基,再与碱中和得到维生素C磷酸酯镁。通过单因素实验,讨论了第一步反应中原料配比(维生素C与丙酮),反应温度,反应时间对中间产物收率的影响,第二步反应中原料配比(5,6-O-异丙叉维生素C与三氯氧磷),催化剂用量和溶液pH对产品维生素C磷酸酯镁收率的影响,获得了适宜的反应条件:反应温度为25℃,反应时间4小时,维生素C与丙酮摩尔配比为15:1,在该反应条件下,5,6-O-异丙叉维生素C收率达到82.94%;5,6-O-异丙叉维生素C与三氯氧磷摩尔配比为1:1.4,5,6-O-异丙叉维生素与吡啶的摩尔配比为1:6,溶液pH为12时,在该反应条件下,维生素C磷酸酯镁的收率达到78.62%。按饲料添加剂,食品添加剂行业标准,采用红外光谱,核磁共振谱等方法对产品进行了定性鉴定。更多还原

【Abstract】 Ascorbyl polyphosphate and its magnesium salts are not only stable, but also good to play the role of ascorbic acid, so which are widely used in feed addivites, food nutrition additives, cosmetic whitening additives, medicine auxiliary preparation and so on.Along with the enhancement of people’s living standards, ascorbyl polyphosphate and its magnesium salts has even greater demand for space. In view of the existing post- processing techniques of ascorbic acid phospate magnesium, the low energy consumption process of hydrolysis removal of protecting group in the acidic conditions was proposed in the article.1. Take ascorbic acid as raw material, sodium trimetaphosphat as phosphorylation agent, calcium chloride as catalyst, ascorbyl polyphosphate was prepared through esterifying reactions in polar solvement water system. Through single factor and orthogonal experiment, the ratio of raw materials (ascorbic acid to sodium trimetaphosphat), reaction temperature, amount of catalyst and pH of the solution on the yield of ascorbyl polyphosphate were discussed, and obtained the optimal reaction conditions:The results showed that the reaction temperature was 35℃, the mole ratio of ascorbic acid and sodium trimetaphosphat was 1.0:1.3, the mole ratio of ascorbic acid and calcium chloride was 1:0.15, pH of the solution was 9, at which experimental conditions, the yield of ascorbyl polyphosphate could be up to 76.58%.2. Take ascorbic acid as raw material, using the methods of group protection, frist reacting ascorbic acid with acetone to prepare 5,6-isopropylideneascorbic acid, then with phosphoryl chloride as phosphorylation agent, pyridine as catalyst, occurred phosphorylation reactions under alkaline conditions and removed protecting group through hydrolyzed in acidic conditions, then neutralized with alkali to prepare ascorbyl polyphosphate. Through single factor experiment, the ratio of raw materials (ascorbic acid to actone), reaction temperature and reaction time to the yield of intermediate product in the first step were investigated, the ratio of raw materials (5,6-isopropylideneascorbic acid to phosphoryl chloride), amount of catalyst and pH of the solution on the yield of ascorbyl polyphosphate in the second step were also discussed, and obtained a appropriate experimental conditions.The results showed that the reaction temperature was 25℃, the mole ratio of ascorbic acid and actone was 15:1, the mole ratio of ascorbic acid and the reaction time was 4h, at which experimental conditions, the yield of 5,6-isopropylideneascorbic acid could be up to 82.94%; the mole ratio of 5,6-isopropylideneascorbic acid and phosphoryl chloride was 1:1.4, the mole ratio of 5,6-isopropylideneascorbic acid and pyridine was 1:6, pH of the solution was 12, at which experimental conditions, the yield of ascorbyl polyphosphate could be up to 78.62%.According with the industry standards of feeding additives, the product was qualitative identified by way of infared (IR) spectrum and nuclear magnetic resonance (NMR).更多还原