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

Synthesis of Ethylene Carbonate via Carbon Dioxide and Ethylene Oxide Catalyzed by Immobilized Ionic Liquid

用溴化1-羟乙基-3-乙烯基咪唑、甲基丙烯酸钠、丙烯酸羟乙酯、苯乙烯4种单体共聚合成了高分子离子液体催化剂,表征了其结构.将该催化剂固载到分子筛上制成固体颗粒催化剂,催化环氧乙烷(EO)与CO2合成碳酸乙烯酯(EC)的反应,考察了反应时间、温度、压力、催化剂用量对EO转化率及生成EC选择性的影响.结果表明,在反应时间4h、温度403.15K、压力2.5MPa、催化剂与环氧乙烷质量比9%的条件下,EO转化率为95%,EC选择性为98%,催化剂在循环使用10次后,EO转化率无明显下降,EC选择性接近100%.该反应为一级反应,动力学方程为r=-dCEO/dt=9.872×104e-52.00/(CEO.RT)

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.