环氧丙烷、二氧化碳和甲醇催化合成碳酸二甲酯

Direct Synthesis of Dimethyl Carbonate from Propylene Oxide, Carbon Dioxide and Methanol over Solid Catalysts

在KI/γ-Al2O3催化剂基础上,制备了负载型固体碱催化剂并对其催化环氧丙烷(PO),CO2和甲醇直接合成碳酸二甲酯(DMC)反应的活性进行了评价,发现K2O/4A分子筛的活性最好,碳酸二甲酯的收率达18.4%,高于现有文献值。实验表明,产物DMC是由PO和CO2生成的碳酸丙烯酯(PC)与甲醇进行酯交换所生成的,甲醇对PO和CO2合成PC反应具有助催化作用。

Catalytic activity of KI/γ-Al_2O_3, KI-Ti(OH)_4/γ-Al_2O_3 and some solid alkali for direct synthesis of dimethyl carbonate (DMC) from propylene oxide, carbon dioxide and methanol has been evaluated. Among the above solid catalysts, the activity of KI-Ti(OH)_4/γ-Al_2O_3 was better than that of KI/γ-Al_2O_3. And K_2O/4A molecular sieve showed the highest activity; yield of DMC reached 18.4%, which is higher than that in the literatures so for. In addition, the investigation to reaction mechanism illustrated that DMC is formed from the esterification of methanol and propylene carbonate (PC) resulted from PO and carbon dioxide. Furthermore, methanol plays role of a promoter for the synthesis of PC from PO and carbon dioxide.