Supported palladium catalysts, which were used in the oxidative esterification of methacrolein to methyl methacrylate, have been prepared with different carriers and Pd precursors. Experimental results revealed that P...Supported palladium catalysts, which were used in the oxidative esterification of methacrolein to methyl methacrylate, have been prepared with different carriers and Pd precursors. Experimental results revealed that Pd catalysts with γ-Al2O3 support and Na2PdCl4 precursor showed good performance. Pd catalyst modified with Pb and Mg indicated that Pd-Mg bimetallic catalyst exhibited considerably higher activity and Pd-Pb exhibited both higher activity and selectivity. 92.27% methacrolein conversion and 90.57% methyl methacrylate selectivity were obtained on Pd-Pb-Mg catalyst.展开更多
Vapor-phase nitration of benzene over solid acid catalyst is expected to be a clean process with no sulfuric acid waste. We investigated this process over solid acidic catalysts utilizing diluted nitric acid (60-70%) ...Vapor-phase nitration of benzene over solid acid catalyst is expected to be a clean process with no sulfuric acid waste. We investigated this process over solid acidic catalysts utilizing diluted nitric acid (60-70%) as nitrating agent, and found that supported sulfuric acid catalyst exhibited a very high catalytic activity. Under the conditions of reaction temperature 160-170℃, space velocity (SV) 1200 h-1, the yield and the space-time yield (STY) of nitrobenzene (NB) based on HNO3 were more than 98% and 0.75 kg穔gcat-1穐-1 over 10% H2SO4/SiO2 (by weight) catalyst respectively.展开更多
基金Financial supported by the National Natural Science Foundation of China (No.20436050)Foundation of Graduate University of the Chinese Academy of Sciences.
文摘Supported palladium catalysts, which were used in the oxidative esterification of methacrolein to methyl methacrylate, have been prepared with different carriers and Pd precursors. Experimental results revealed that Pd catalysts with γ-Al2O3 support and Na2PdCl4 precursor showed good performance. Pd catalyst modified with Pb and Mg indicated that Pd-Mg bimetallic catalyst exhibited considerably higher activity and Pd-Pb exhibited both higher activity and selectivity. 92.27% methacrolein conversion and 90.57% methyl methacrylate selectivity were obtained on Pd-Pb-Mg catalyst.
文摘Vapor-phase nitration of benzene over solid acid catalyst is expected to be a clean process with no sulfuric acid waste. We investigated this process over solid acidic catalysts utilizing diluted nitric acid (60-70%) as nitrating agent, and found that supported sulfuric acid catalyst exhibited a very high catalytic activity. Under the conditions of reaction temperature 160-170℃, space velocity (SV) 1200 h-1, the yield and the space-time yield (STY) of nitrobenzene (NB) based on HNO3 were more than 98% and 0.75 kg穔gcat-1穐-1 over 10% H2SO4/SiO2 (by weight) catalyst respectively.