The propylene epoxidation over TS-1/SiO2 catalyst hydrothermally treated was investigated. It was found by EPR characterization that two types of Ti (IV)-superoxide radicals, A (gz=2.0271; gy=2.0074; gx=2.0010) and ...The propylene epoxidation over TS-1/SiO2 catalyst hydrothermally treated was investigated. It was found by EPR characterization that two types of Ti (IV)-superoxide radicals, A (gz=2.0271; gy=2.0074; gx=2.0010) and B (gz=2.0247; gy= 2.0074; gx= 2.0010), were observed for TS-1/SiO2. The superoxo species A converted to B after TS-1/SiO2 catalyst was hydrothermally treated. The results show that over TS-1/SiO2 catalyst hydrothermally treated at 170℃, about 95% conversion of H2O2 with above 94% PO selectivity is obtained during continuous running for 300 h under the conditions of reaction temperature 45℃, 0.5 h-1WHSV of propylene.展开更多
基金Supported by the National Key Basic Research Project of China(G2000048009)the Doctorate Foundation of Liaoning Province(2001102085)
文摘The propylene epoxidation over TS-1/SiO2 catalyst hydrothermally treated was investigated. It was found by EPR characterization that two types of Ti (IV)-superoxide radicals, A (gz=2.0271; gy=2.0074; gx=2.0010) and B (gz=2.0247; gy= 2.0074; gx= 2.0010), were observed for TS-1/SiO2. The superoxo species A converted to B after TS-1/SiO2 catalyst was hydrothermally treated. The results show that over TS-1/SiO2 catalyst hydrothermally treated at 170℃, about 95% conversion of H2O2 with above 94% PO selectivity is obtained during continuous running for 300 h under the conditions of reaction temperature 45℃, 0.5 h-1WHSV of propylene.
