Synthesis Of Co(Ca)-SBA-15and Their Catalytic Properties

Both styrene oxide and styrene carbonate are important intermediate compounds,which are extensively used in the pharmaceuticals and fine chemicals fields. Styreneoxide is obtained from the epoxidation of styrene, and styrene carbonate is synthesizedby the cycloaddition reaction between CO₂and styrene oxide.Metal supported the mesoporous materials and ionic liquids are extensively used inthe catalytic reactions. Herein, we synthesized metals supported mesoporous materialsand investigated their catalytic activity. Moreover, catalytic activities over variousquaternary ammonium （phosphorus） salts with different alkyl chain lengths wasinvestigated in the cycloaddition reaction between CO₂and styrene oxide.First of all, we synthesized Co-SBA-15and Ca-SBA-15with different metalloadings by one-pot synthesis method, urea adjusting method, pH adjusting method,impregnation method and solvent evaporation self-assembly method. Variouscharacterizations such as XRD, FT-IR, UV-vis spectroscopy, N2adsorption-desorptionisotherms measurement and SEM were determined to verify the textual structure andphysicochemical properties. The results showed that pH adjusting method is the bestmethod to synthesize Co-SBA-15, both impregnation method and solvent evaporationself-assembly method are effective method to synthesize Ca-SBA-15.Then Co-SBA-15was used as catalyst in the reaction of epoxidation of styrene, andinfluence factors such as synthesis method and reaction time were investigated. Itsuggests that Co-SBA-15synthesized by pH adjusting method showed the best catalystactivity, the catalyst activity enhanced with the increases of the metal contents, theselectivity of styrene oxide achieved the maximum at4h, of71.8%. Moreover, thecatalytic activities over quaternary ammonium （phosphorus） salts with different alkylchain lengths in the cycloaddition reaction between CO₂and styrene oxide were studied.Among all the ionic liquids, TBAB showed the best activity. At the optimum reactionconditions, the conversion rate of styrene oxide was96.7%, the yield of styrenecarbonate were95.7%, respectively. At last, Ca-SBA-15was tested as catalyst in thecycloaddition reaction between CO₂and styrene oxide.