基于DFT计算的1,4-丁二醇脱水反应过程分析

The dehydration reaction mechanism of 1,4-butanediol and the regulation mechanism of catalyst were studied using Gaussian 09 based on the DFT theory and transition state theory, and the thermodynamic parameters of the 1,4-butanediol reaction network were calculated. The elementary steps were determined by searching the transition state and pathway of each reaction. The strategies of both catalyst design and reaction process intensification were also clarified. Results show that the reaction network was under kinetic control within the studied temperature range due to large equilibrium constants. Kinetic studies indicated that the parallel side reaction of tetrahydrofuran formation and the tandem side reaction of 1,3-butadiene formation greatly influenced the selectivity of 3-buten-1-ol due to their low potential energy barriers. The terminal hydroxyl group and β-H can be simultaneously activated by designing an acid-base bifunctional catalyst to make 1,4-butanediol dehydrating to 3-buten-1-ol more easily. Meanwhile, the method of reducing the residence time of 3-buten-1-ol could be used to suppress the occurrence of tandem side reactions.