摘要
Rhodium- and iron phosphate-based catalysts are by far the most promising catalysts for oxy-bromination of methane(OBM) reaction. However, most literature reported either Rh- or FePO4-based catalysts, and the results were rarely studied in a uniform environmental condition. In this report, comparative study was conducted on silica- and silicon carbide-supported rhodium and iron phosphate catalysts with the main focuses on stability performance and coke deposition. The catalytic results demonstrated that the stability of both Rh- and FePO4-based catalysts was greatly influenced by the supports used, and silicon carbide-supported catalysts showed much better anti-coking ability as compared with silica-supported ones. Temperature-programmed oxidation over the used catalysts further indicated that the coke formation mechanisms were completely different between silica-supported rhodium and iron phosphate catalysts. While cokes might be caused by condensation of CH2Br2over supported iron phosphate, methane decomposition might be the reason for coke formation over silica-supported rhodium catalyst. These findings might pave the way for designing highly efficient and stable catalysts of the OBM reaction.
Rhodium- and iron phosphate-based catalysts are by far the most promising catalysts for oxy-bromination of methane(OBM) reaction. However, most literature reported either Rh- or FePO4-based catalysts, and the results were rarely studied in a uniform environmental condition. In this report, comparative study was conducted on silica- and silicon carbide-supported rhodium and iron phosphate catalysts with the main focuses on stability performance and coke deposition. The catalytic results demonstrated that the stability of both Rh- and FePO4-based catalysts was greatly influenced by the supports used, and silicon carbide-supported catalysts showed much better anti-coking ability as compared with silica-supported ones. Temperature-programmed oxidation over the used catalysts further indicated that the coke formation mechanisms were completely different between silica-supported rhodium and iron phosphate catalysts. While cokes might be caused by condensation of CH2Br2over supported iron phosphate, methane decomposition might be the reason for coke formation over silica-supported rhodium catalyst. These findings might pave the way for designing highly efficient and stable catalysts of the OBM reaction.
基金
supported by the National Natural Science Foundation of China(Grant No.21103170)
