文档介绍：固体杂多酸催化合成苯甲酸异丁酯
辽宁石油化工大学继续教育学院论文
学院
毕业设计(论文)
Heteropolyacid
院(系)名称
专业名称
学生姓名
学号学院化学工程与工艺王新峰
徐晓强教授指导教师
年月日
辽宁石油化工大学继续教育学院论文
苯甲酸异丁酯为无色油状液体,具有清甜气息,对人身安全没有潜在危险,不污染环境,经合理配伍可制成各种香型的香精,用于食品,还广泛用于配置各种香水、化妆品等,近年来已受到越来越多的关注。
本论文用固体杂多酸为催化剂对苯甲酸异丁酯的合成进行了研究。在实验过程中发现:%-%之间时,酯化率随催化剂用量加大而增加,当催化剂用量进一步加大,酯化率没有太大的变化;在反应时间为6小时前,酯化率随时间的增加而逐步增大,6小时以后,酯化率几乎不变;醇酸比为2-4时酯化率变化不大,在醇酸比为4时,%,进一步提高醇酸比,则酯化率有较大幅度下降;
带水剂甲苯用量为20 ;而用苯和环己烷做带水剂时,酯化率大幅度降低。
由此得到结论:以磷钨酸为催化剂,%,醇酸比为4,回流分水时间6 h,反应温度108 ℃~112 ℃,,%。
关键词:苯甲酸异丁酯;合成;固体杂多酸;催化酯化;工艺条件
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辽宁石油化工大学继续教育学院论文
Abstract
Isobutyl benzoate is a colorless, oil-like liquid with sweet smell. It is harmless and has no potential risk to personal safety. Various flavors of essences can be made by patibility of it with other materials, and can be widely used in various configurations perfume, cosmetics etc. In recent years it has been abstracting more and more attention.
The synthesis of isobutyl benzoate by esterification of benzoic acid and isobutyl alcohol catalyzed by solid heteropolyacid with water stripping agents was studied. The effects of type and amount of catalysts, reaction time, molar ratio of reactants and type and amount of water stripping agents on the yield of isobutyl benzoate were investigated. The experimental results showed that when the amount of catalyst was increased form % to % of the benzoic acid, the yield increased from % to %. Further increase of
the amount of catalyst did not change the yield significantly. The yield increased with the reaction time till six hours. After six hours, the yield was almost kept constant. The yield reached % when molar ratio of reactants was 4, while the yield was % or % when the ratio was 2 or 3 respectively. Yield of % was obtained with toluene as the water stripping agents, which was higher than that with ben