季铵盐和叔胺协同催化一步酯交换法合成碳酸二甲酯的研究

Synergistic catalytic performance of quaternary ammonium salt and tertiary amine for synthesis of dimethyl carbonate by one-step transesterification

以不同季铵盐和叔胺为催化剂,考察了它们各自和协同催化甲醇、CO2和环氧丙烷(PO)或环氧氯丙烷(ECH)一步法合成碳酸二甲酯(DMC)的催化性能。结果表明,季铵盐对一步法合成DMC中第一步反应(即CO2和PO环加成反应生成环状碳酸酯)的催化性能较好,而叔胺对一步法合成DMC中第二步反应(即环状碳酸酯与甲醇反应生成DMC)的催化效果较好。其中,以双十六烷基二甲基溴化铵(DHDMAB)和N,N-二烯丙基甲基胺(MDAA)分别为季铵盐和叔胺的协同催化性能最佳,其DMC产率达35.2%。此外,以PO为环氧化合物的DMC产率远高于ECH。

Quaternary ammonium salt and tertiary amine were used as catalysts, and their respective and synergistic catalytic per- formance for synthesis of dimethyl carbonate by one-step transesterification from CO2, methanol and propylene oxide （PO）or epi- chlorohydrin（ ECH）were investigated in detail. The results indicated that quaternary ammonium salt presented a good catalytic per- formance for the first reaction of DMC synthesis（ i. e. ,CO2 reacted with PO to form cyclic carbonate） ,while tertiary amine presen- ted a good catalytic performance for the second reaction of DMC synthesis （ i. e. , methanol reacted with cyclic carbonate to form DMC）. Thereinto, the catalytic performance of dihexadecyldimethylammonium bromide （ DHDMAB ） and methyldiallylamine （DMAA） ,used as quaternary ammonium salt and tertiary amine,respectively,presented the best synergistic effect,and the yield of DMC reached 35.2%. Moreover, DMC yields of PO used as epoxide were higher than those of ECH used as epoxide.