SBA-15负载咪唑盐离子液体催化剂用于CO_(2)环加成反应的失活机理研究

Deactivation Mechanism of SBA-15 Supported Imidazole Ionic Liquids Catalyst Used in CO_(2) Cycloaddition Reaction

采用后嫁接法将咪唑盐离子液体负载在SBA-15上制备了多相催化剂SBA-15-Imi并将其用于CO_(2)环加成反应,研究了介孔氧化硅负载离子液体催化剂的失活机理。采用XRD、SEM、TEM、TG、FT-IR、EA等多种表征手段探究了潜在的失活原因;同时将基于分形理论、Porod理论的SAXS数据用于催化剂失活原因的分析,对催化剂的微观结构进行深入的研究。结果表明:催化剂循环使用5次后产率降低了74%,失活原因主要是离子液体流失及有机物杂质沉积。

Imidazolium ionic liquids were immobilized on SBA-15(SBA-15-Imi)via post-grafting method to prepare heterogeneous catalyst for CO_(2)cycloaddition reaction to investigate the deactivation mechanism of mesoporous silica supported ionic liquids catalyst.Then,various characterization methods such as XRD,SEM,TEM,TG,FT-IR,EA,etc.were employed to explore the potential causes of deactivation.Besides,SAXS based on fractal theory and Porod theory was used to analyze both the fresh and recycled catalysts to demonstrate the microstructure changes after reaction.The results showed that the yield of SBA-15-Imi decreased by 74%after 5 cycles of use,the primary reason of deactivation was the loss of ionic liquids,and the organic deposition.