碱性离子液体催化合成三羟甲基丙烷

以碱性离子液体为催化剂, 构建了一种新型、高效的合成三羟甲基丙烷(TMP)的方法. 系统考察了催化剂类型、催化剂用量、反应温度、反应时间、甲醛与正丁醛用量比等因素对三羟甲基丙烷分离收率的影响. 研究结果表明: 碱性离子液体的催化性能与其碱强度息息相关, 碱性越强、催化活性越高. 最优条件下, 经离子液体bmim]OH催化后, 可得到84%的TMP分离收率, 这一结果优于传统的有机无机碱催化体系且成功规避了传统碱催化合成TMP过程中繁琐的除盐过程、降低了过程能耗. 此外, 离子液体催化剂和未反应的丁醛均表现了良好的重复使用性能.

Catalytic Synthesis of Trimethylolpropane in the Presence of Basic Ionic Liquid

Ionic liquid (IL) catalyst attracts increasing attention during last few decades due to its excellent advantages of both homogeneous and heterogeneous catalyst. Here, a novel and efficient strategy for the production of trimethylolpropane (TMP) is proposed with basic IL catalysts. The catalytic activities of the IL catalysts are investigated. The effects of catalyst dosage, reaction temperature, time, and the molar ratio of the reactants are also studied. The results show that the basicity of the IL catalyst has a significant effect on the catalytic activity, where stronger basicity indicates higher catalytic activity. The IL 1-butyl-3-methyl imidazolium hydroxyl (bmim]OH) is proven to be the most efficient catalyst where more than 84% isolated yield of TMP was obtained under optimized conditions. Furthermore, both the IL catalyst and butyraldehyde show excellent recyclability. Moreover, this IL catalytic system avoids the inevitable desalination encountered by current processes utilizing inorganic alkali catalysts.