Supported quaternary phosphonium catalysts were prepared with N,N-dimethyl formamide(DMF) as the solvent,which replaced toluene due to its higher boiling point,and used in the synthesis of ethylene carbonate(EC) from ethylene oxide(EO) and CO2.The effects of supports,quaternary phosphonium ions and coordinating anions on the performances of the catalysts were investigated.It was found that the appropriate conditions for the catalyst preparation were chloromethylated polystyrene as the support,triphenylphosphine as the tertiary phosphine source,DMF as the solvent and I as the coordinating anion.Under the optimized reaction conditions of the mass ratio of EO to the catalyst 6.6,100 ℃,2.5 MPa and 2 h,the conversion of EO and the selectivity to EC can reach 98.4％ and 99.6％,respectively.The catalyst can be reused 5 times without the obvious activity decay.%用沸点较高的N,N-二甲基甲酰胺(DMF)取代甲苯作为溶剂高效合成了负载型季鏻盐催化剂,并将该催化剂用于环氧乙烷(EO)与CO2合成碳酸乙烯酯(EC).对催化剂载体、季鏻盐离子和配位阴离子的种类进行了筛选,优化了合成EC的工艺条件,并考察了催化剂的重复使用性能.实验结果表明,适宜的催化剂制备条件为:氯甲基化的聚苯乙烯作为催化剂载体,三苯基膦作为合成季鏻盐的叔膦,DMF作为溶剂,I作为配位阴离子；该催化剂用于合成EC的最佳工艺条件为:EO与催化剂的质量比6.6,反应温度100 ℃,反应压力2.5 MPa,反应时间2h；在该条件下,EO转化率为98.4％,EC选择性为99.6％；催化剂重复使用5次活性无明显下降,显示了良好的工业应用前景.
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