Synthesis of Ethylene Carbonate via Carbon Dioxide and Ethylene Oxide Catalyzed by Immobilized Ionic Liquid
固载化离子液体催化环氧乙烷和二氧化碳合成碳酸乙烯酯

A new polymer ionic liquid catalyst PMHS-HEVIMBr was synthesized by four monomers of bromide 1-hydroxyethyl-3-vinyl imidazole (HEVIMBr), sodium methacrylate, 2-hydroxyethyl acrylate and styrene, and characterized in its structure. Then, the polymer ionic liquid was immobilized on the molecular sieve as solid catalyst particles for synthesis of ethylene carbonate (EC) via reaction of ethylene oxide (EO) with CO2. The effects of reaction time, temperature, pressure, catalyst concentration on the EO conversion rate and EC selectivity were examined. The results indicated that 95% of EO conversion rate and 98% of EC selectivity could be reached at the optimal conditions of reaction time 4 h, pressure 2.5 MPa, temperature 403.15 K and mass ratio of catalyst to EO 9%. The catalyst activity remained stable after 10 times of recycle, EO conversion rate had no significant loss, EC selectivity was close to 100%. The kinetic equation on the catalytic reaction process was obtain, r=-dCEO/dt=9.872×104e-52.00/(RT)CEO.