硫酸氢钾催化合成异戊酸丁酯

摘要

using potassium bisulfate as the heterogeneous catalyst,isovaleric acid and n-butanol reacted to form flavor butyl isovalerate.Factors influencing the yield were discussed.That amount of catalyst,reaction time,molar ratio of alcohol to acid,different water carrying agents and the time of repeated uses were investigated.Experiment results showed that the catalyst had many advantages such as insoluble in reaction system,high activity,short reaction time,lower cost and easy post treatment.It was an efficient,economic and environmental friendly catalyst.The best conditions were isovaleric acid 0.2mol,molar ratio of alcohol to acid 1.4,the catalyst 1.5g,toluene 5mL and reaction time 60min.The yield could reach 92.5%.%以异戊酸和正丁醇为原料,采用不溶于反应物系的硫酸氢钾为非均相催化剂合成了食用香料异戊酸丁酯.考察了催化剂用量、醇酸物质的量比、回流反应时间、催化剂重复使用性及带水剂种类等因素对目标产物收率的影响.结果表明该催化剂具有催化活性高,反应时间短,出水速率快,价廉易得,稳定性好,合成工艺流程简单,操作方便,不易腐蚀设备等诸多优势.由于该催化剂难溶于反应物系,因而易分离回收,废液排放量少,回收的催化剂不经任何活化处理便有良好的重复使用性.硫酸氢钾是合成异戊酸丁酯高效、经济且环境友好的非均相催化剂,具有一定工业化应用前景.适宜反应条件为:异戊酸0.2mol,正丁醇与异戊酸物质的量比1.4,催化剂1.5g,回流反应时间60min,带水剂甲苯5mL,产品收率达92.5%.