活性炭负载磷钨酸催化合成丁酸异丁酯

摘要

采用活性炭负载磷钨酸为催化剂,以丁酸和异丁醇为原料合成丁酸异丁酯,考察了催化剂负载量、醇酸摩尔比,催化剂用量、反应时间及催化剂重复使用次数等因素对酯化率的影响.适宜的反应条件为:丁酸用量0.1 mol,醇酸摩尔比1.4:1,催化剂用量0.8g,催化剂负载量20.2％,回流反应时间70 min,酯化率达到99.2％.该催化剂有良好的重复使用性,使用5次后酯化率达95.8％.%By using activated carbon supported tungstophosphoric acid as a catalyst, butyric acid and isobutyl alcohol reacted to form isobutyl butyrate. The effects such as supported weight of tungstophosphoric acid, molar ratio of isobutyl alcohol to butyric acid, amount of catalyst, reaction time and repeated using times of the catalyst on the rate of esterification were discussed. The optimum reaction conditions were found as follows: butyric acid 0. 1 mol, n(isobutyl alcohol) : n(butyric acid) = l. 4 : 1, tungstophosphoric acid catalyst (with supported weight 20. 2%) of 0. 8 g, refluxing reaction time of 70 min. Under the optimum conditions, the rate of esterification is 99. 2%. The catalyst could be used repeatedly and the fifth rate of esterification could still reach 95. 8%.