Catalytic Conversion of Carbon Dioxide to Propylene Carbonate: Catalyst Design and Industrialization Progress

Converting CO2 into valuable chemicals is an effective way to alleviate the high level of global CO2. The cycloaddition reaction of CO2 and propylene oxide (PO) has atomic economy and has the advantage of environmental friendliness compared with the traditional phosgene method of propylene carbonate (PC). Due to the chemical inertness of CO2, catalysts are needed to make the reaction proceed smoothly. Through rational design, a multifunctional catalyst that combines the activation sites and attack sites of PO and the adsorption sites of CO2 can be formed. At the same time, the use of harmful substances can be reduced by catalyst design, making the catalytic process more environmentally friendly. In this work, we discuss the research progress of the synthesis of PC from CO2 and PO. Starting from the reaction mechanism, the catalytic system of the reaction is summarized from the perspective of catalyst design. In homogeneous catalysts, the focus is on the effect of catalyst composition on catalytic performance. In heterogeneous catalysts, the focus is on the process of heterogenization (preparation methods), including supported, confined, and polymerized heterogeneous catalysts. In addition, the promising photocatalysis and biomass catalysis are especially introduced. Finally, in order to make the experimental results move toward industrial production, several problems existing in the industrialization are discussed, including production equipment, the influence of the CO2 source, and product/catalyst separation.