高取代度魔芋葡甘聚糖磷酸酯的干法制备

Dry Preparation of Konjac Glucomannan Phosphate Ester with High Degree of Substitution

[目的]研究高取代度魔芋葡甘聚糖磷酸酯的干法制备,为其多糖衍生物实际应用于絮凝、离子交换等领域提供参考。[方法]以细化的魔芋粉为原料,以NaH2PO4和Na2HPO4混合物为磷酸酯化试剂,在干法条件下,制备魔芋葡甘聚糖磷酸酯,并采用正交试验法优化魔芋葡甘聚糖磷酸酯最佳工艺。[结果]正交试验结果表明,影响魔芋葡甘聚糖磷酸酯取代度因素次序依次为磷酸盐用量>反应温度>反应时间>磷酸盐配比>催化剂用量>pH值。制备高取代度魔芋葡甘聚糖磷酸酯的最佳工艺条件:磷酸盐用量为3.50%,反应温度为170℃,反应时间为4 h,NaH2PO4和Na2HPO4摩尔比为1∶2,催化剂用量为3.00%,pH值为4.00;魔芋葡甘聚糖磷酸酯取代度达0.17。[结论]该方法获得较高取代度的魔芋葡甘聚糖磷酸酯可以应用于实际生产。

[ Objective ] The aim was to research the dry preparation of konjac glucomannan phosphate ester with high degree of substitution, and provide reference for application of its polysaccharide derivatives in flocculation, ion exchange and other fields. [ Method ] Taking refined konjak powder as raw material, taking the mixture of NaH2PO4 and Na2HPO4 as phosphate esterification reagent, the konjae glucomannan phosphate ester was prepared under the dry condition, and the optimal process of konjac glucomannan phosphate ester was optimized by orthog- oua] test method. [ Result ] The result of orthogonal test showed that the factor orders of affecting the substitution degree of konjac glueomannan phosphate ester were that： phosphate amount 〉 reaction temperature 〉 reaction time 〉 ratio of phosphate 〉 catalyst amount 〉 pH value. The optimal process condition of preparing the konjac glueomannan phosphate ester with high degree of substitution was that ： the phosphate amount was 3.50%, the reaction temperature was 170 ℃, the reaction time was 4 h, the ratio of Nai12 PO4 and Na2 HPO4 was 1：2, the catalyst amount was 3.00% and pH value was 4.00. The substitution degree of konjac glucomannan phosphate ester reached to 0. 17. [ Conclusion] This method can get konjac glucommman phosphate ester with high degree of substitution and can be applied in practical production.