The selective oxidation of n-butane to maleic anhydride (MA) on a vanadium-phosphorus oxide (VPO) catalyst was studied using on-line gas-chromatography combined with mass spectrometry(GC-MS) and transient response tec...The selective oxidation of n-butane to maleic anhydride (MA) on a vanadium-phosphorus oxide (VPO) catalyst was studied using on-line gas-chromatography combined with mass spectrometry(GC-MS) and transient response technique. The reaction intermediates, buterie and furan, were found in the reaction effluent under near industrial feed condition (3% butane+15%O2), while dihydrofuran was detected at high butane concentration (12% butane, 5%O2). Some intermediates of MA decomposition were also identified. Detection of these intermediates shows that the vanadium phosphorus oxides are able to dehydrogenate butane to butene, and butene further to form MA. Based on these observations, a modified scheme of reaction network is proposed. The transient experiments show that butane in the gas phase may directly react with oxygen both on the surface and from the metal oxide lattice, without a proceeding adsorption step. Gas phase oxygen can be adsorbed and transformed to surface lattice oxygen but it can not participate in selective oxidation. Adsorbed oxygen leads to deep oxidation, while lattice oxygen leads to selective oxidation.展开更多
An efficient catalytic system was successfully developed on reduction of A/-heteroaromatics with H3N-BH3 as hydrogen source in CuSO4 solution,featuri ng excel I e nt chemoselectivity as well as very broad functional g...An efficient catalytic system was successfully developed on reduction of A/-heteroaromatics with H3N-BH3 as hydrogen source in CuSO4 solution,featuri ng excel I e nt chemoselectivity as well as very broad functional group tolera nee.Various challe nging substrates,such as OH-,NH_(2)^(-), Cl^(-),Br^(-),etc.,contained quinolines,quinoxalines,1,5-naphthyridines and quinazolines were all reduced smoothly.Mecha nistic studies suggested that[Cu-H]in termediate might be gen erated from NH_(3)·BH_(3)/which was believed to form with H3N-BH3 in CuSO_(4) solution.展开更多
基金Supported by the National Natural Science Foundation of China (No. 29792073-3).
文摘The selective oxidation of n-butane to maleic anhydride (MA) on a vanadium-phosphorus oxide (VPO) catalyst was studied using on-line gas-chromatography combined with mass spectrometry(GC-MS) and transient response technique. The reaction intermediates, buterie and furan, were found in the reaction effluent under near industrial feed condition (3% butane+15%O2), while dihydrofuran was detected at high butane concentration (12% butane, 5%O2). Some intermediates of MA decomposition were also identified. Detection of these intermediates shows that the vanadium phosphorus oxides are able to dehydrogenate butane to butene, and butene further to form MA. Based on these observations, a modified scheme of reaction network is proposed. The transient experiments show that butane in the gas phase may directly react with oxygen both on the surface and from the metal oxide lattice, without a proceeding adsorption step. Gas phase oxygen can be adsorbed and transformed to surface lattice oxygen but it can not participate in selective oxidation. Adsorbed oxygen leads to deep oxidation, while lattice oxygen leads to selective oxidation.
基金Financial support from the National Natural Science Founda-tion of China(Nos.21702065,21772046 and 2193103)the Promotion Program for Young and Middle-aged Teacher in Science and Tech no logy Research of Huaqiao Un iversity is gratefully ackno wledged.
文摘An efficient catalytic system was successfully developed on reduction of A/-heteroaromatics with H3N-BH3 as hydrogen source in CuSO4 solution,featuri ng excel I e nt chemoselectivity as well as very broad functional group tolera nee.Various challe nging substrates,such as OH-,NH_(2)^(-), Cl^(-),Br^(-),etc.,contained quinolines,quinoxalines,1,5-naphthyridines and quinazolines were all reduced smoothly.Mecha nistic studies suggested that[Cu-H]in termediate might be gen erated from NH_(3)·BH_(3)/which was believed to form with H3N-BH3 in CuSO_(4) solution.
