Rh/SiO2 was prepared for the oxidative bromination of methane. The catalyst was prepared by calcination at different temperatures and for different times to obtain catalysts with different specific surface areas for t...Rh/SiO2 was prepared for the oxidative bromination of methane. The catalyst was prepared by calcination at different temperatures and for different times to obtain catalysts with different specific surface areas for the purposes of producing either CH3Br or CH3Br and CO. It was found that the catalyst having a low specific surface area （calcined at relatively high temperature） favors the selective oxidation of methane to prepare CH3Br, while the catalyst having a high specific surface area favors the deeper partial oxidation of methane, which is good for CH3Br and CO preparation, The 650 h on stream life-time test revealed that the catalytic performance of the 0.4Rh/SiO2-900-10 catalyst was excellent. Both methane conversion and CH3Br selectivity kept increasing trends during the life-time test. No matter how serious was the Rh leaching during the reaction, the 0.4Rh/SiO2-900-10 catalyst did not deactivate at all.展开更多
Dimethyl ether （DME） was synthesized from methane through a two-step process, in which CH3Br was prepared from the oxidative bromination reaction of methane in the presence of HBr and oxygen over a Rh-SiO2 catalyst ...Dimethyl ether （DME） was synthesized from methane through a two-step process, in which CH3Br was prepared from the oxidative bromination reaction of methane in the presence of HBr and oxygen over a Rh-SiO2 catalyst and then, in the second step, CH3Br was hydrolyzed to DME over a silica supported metal chloride catalyst. 12 mol%ZnCl2/SiO2 catalyst was found to be the most active, but it deactivated because of Cl- losing.展开更多
基金supported by the Chinese Ministry of Education Project No.107132the Chinese Ministry of Science and Technology Project No.2005CB221406, 2006BAE02B05
文摘Rh/SiO2 was prepared for the oxidative bromination of methane. The catalyst was prepared by calcination at different temperatures and for different times to obtain catalysts with different specific surface areas for the purposes of producing either CH3Br or CH3Br and CO. It was found that the catalyst having a low specific surface area （calcined at relatively high temperature） favors the selective oxidation of methane to prepare CH3Br, while the catalyst having a high specific surface area favors the deeper partial oxidation of methane, which is good for CH3Br and CO preparation, The 650 h on stream life-time test revealed that the catalytic performance of the 0.4Rh/SiO2-900-10 catalyst was excellent. Both methane conversion and CH3Br selectivity kept increasing trends during the life-time test. No matter how serious was the Rh leaching during the reaction, the 0.4Rh/SiO2-900-10 catalyst did not deactivate at all.
基金supported by the Chinese Ministry of Education Project No.107132the Chinese Ministry of Science and Technology Project No.2006BAE02B05,2005CB221406
文摘Dimethyl ether （DME） was synthesized from methane through a two-step process, in which CH3Br was prepared from the oxidative bromination reaction of methane in the presence of HBr and oxygen over a Rh-SiO2 catalyst and then, in the second step, CH3Br was hydrolyzed to DME over a silica supported metal chloride catalyst. 12 mol%ZnCl2/SiO2 catalyst was found to be the most active, but it deactivated because of Cl- losing.
