尼泊金丁酯绿色合成新工艺

摘要

Butyl paraben was prepared by microwave assisted synthesis,macroporous resin was a catalysis in the reaction of p-hydroxybenzoic acid and n-butanol.The effects of different factors such as catalyst type,mole ratio of reactants,the dosage of catalyst,microwave power,reaction temperature,reaction time and water-carrying agent on the yield of butyl paraben were investigated.The optimum conditions was:p-hydroxybenzoic acid 0.1mol,the molar ratio of n-butanol to p-hydroxybenzoic acid 2.5 : 1,NKC-9 macroporous resin catalyst 30%(based on the total feed stock),Microwave power 425w,reaction temperature 90℃,reaction time 20min,no extra water-carrying agent was needed.Under those conditions,the yield of butyl paraben could reach up to 96.8%.The replacement of catalyzer acid to macroporous resins simplified the production process,and inhibited equipment erosion and environmental pollution.Therefore,macroporous resins were more clean and environmental friendly catalysts.The final products had higher purity and can be reused after simple treatment.The characteristics of the final products was also studied by testing melting point and IR.%研究了以尼泊金酸和正丁醇为原料,大孔树脂为催化剂,微波辅助催化合成尼泊金丁酯的新工艺.探讨了催化剂类型、醇酸摩尔比、催化剂用量、微波功率、微波温度、微波时间、带水剂等因素对合成反应产率的影响,确定了酯化反应的优化工艺条件.实验结果表明:当尼泊金酸用量为0.1mol时,醇酸摩尔比为2.5 : 1,NKC-9大孔树脂用量为反应物总质量的30%,微波炉功率为425w,微波温度90℃,微波时间20min,无需额外添加带水剂,在此条件下酯化反应的产率可达96.8%.大孔树脂代替酸作催化剂简化了生产工艺,避免了设备的腐蚀和环境污染,是更为清洁、环保的绿色酯合成用催化剂.而且产品纯度高,催化剂只经简单处理即可重新投入使用多次.并利用熔点测定、红外光谱等分析手段对产品进行了物性和结构表征.