Kinetic study of CO2 fixation into propylene carbonate with water as efficient medium using microreaction system

Carbon dioxide (CO2) utilization and fixation have become one of the most important research areas nowadays due to the increase of global greenhouse effect. Cyclic carbonate, which is widely used in various fields, can be synthesized by fixation of CO2 with epoxide in industry. Moreover, the synthesis of cyclic carbonate is a 100% atom economical reaction, which makes it eco-friendly and promising. To enhance the reaction efficiency and safety, a microreaction system was used as the platform for cycloaddition reaction. In this work, tetrabutylammonium bromide (TBAB) was chosen as catalyst, and propylene oxide (PO) as a mode substrate. Interestingly, the addition of water can increase the propylene carbonate (PC) yield and decrease the activation energy considerably, proving water as catalyst promoter for PC synthesis. PC yield and selectivity could reach 91.6% and 99.8%, respectively. The Influence factors and kinetic equation for CO2 cycloaddition were obtained as well.