Steam reforming of methanol was carried out on the copper-silica aerogel catalyst.The effects of reaction temperature,feed rate,water to methanol molar ratio and carrier gas flowrate on the H_2 production rate and CO ...Steam reforming of methanol was carried out on the copper-silica aerogel catalyst.The effects of reaction temperature,feed rate,water to methanol molar ratio and carrier gas flowrate on the H_2 production rate and CO selectivity were investigated.M ethanol conversion was increased considerably in the range of about 240-300,after which it increased at a slightly lower rate.The used feed flowrate,steam to methanol molar ratio and carrier gas flowwere 1.2-9.0 m L/h,1.2-5.0 and 20-80 m L/min,respectively.Reducing the feed flowrate increased the H_2 production rate.It was found that an increase in the water to methanol ratio and decreasing the carrier gas flowrate slightly increases the H2production rate.Increasing the water to methanol ratio causes the lowest temperature in which CO formation was observed to rise,so that for the ratio of 5.0 no CO formation was detected in temperatures lower than 375℃.In all conditions,by approaching the complete conversion,increasing the main product concentration,increasing the temperature and contact time,and decreasing the steam to methanol ratio,the CO selectivity was increased.These results suggested that CO was formed as a secondary product through reverse water-gas shift reaction and did not participate in the methanol steam reforming reaction mechanism.展开更多
The SiO2-supported Cu 3/2PMo 12O 40 catalyst was prepared by impregnating SiO2 with the solution of Cu 3/2PMo 12O 40. The catalyst was used for the transesterification of dimethyl carbonate and phenol to form diphenyl...The SiO2-supported Cu 3/2PMo 12O 40 catalyst was prepared by impregnating SiO2 with the solution of Cu 3/2PMo 12O 40. The catalyst was used for the transesterification of dimethyl carbonate and phenol to form diphenyl carbonate, and the effect of the Cu 3/2PMo 12O 40 loading and calcination temperature on the catalytic performance was investigated. The optimum Cu 3/2PMo 12O 40 loading was 26%, and the best calcination temperature was 400 ℃. Under the conditions of 175 ℃ and 8 h, the phenol conversion and the transesterification selectivity over 22%Cu 3/2PMo 12O 40/SiO2 calcined at 400 ℃ were 25% and 99.2%, respectively.展开更多
文摘Steam reforming of methanol was carried out on the copper-silica aerogel catalyst.The effects of reaction temperature,feed rate,water to methanol molar ratio and carrier gas flowrate on the H_2 production rate and CO selectivity were investigated.M ethanol conversion was increased considerably in the range of about 240-300,after which it increased at a slightly lower rate.The used feed flowrate,steam to methanol molar ratio and carrier gas flowwere 1.2-9.0 m L/h,1.2-5.0 and 20-80 m L/min,respectively.Reducing the feed flowrate increased the H_2 production rate.It was found that an increase in the water to methanol ratio and decreasing the carrier gas flowrate slightly increases the H2production rate.Increasing the water to methanol ratio causes the lowest temperature in which CO formation was observed to rise,so that for the ratio of 5.0 no CO formation was detected in temperatures lower than 375℃.In all conditions,by approaching the complete conversion,increasing the main product concentration,increasing the temperature and contact time,and decreasing the steam to methanol ratio,the CO selectivity was increased.These results suggested that CO was formed as a secondary product through reverse water-gas shift reaction and did not participate in the methanol steam reforming reaction mechanism.
文摘The SiO2-supported Cu 3/2PMo 12O 40 catalyst was prepared by impregnating SiO2 with the solution of Cu 3/2PMo 12O 40. The catalyst was used for the transesterification of dimethyl carbonate and phenol to form diphenyl carbonate, and the effect of the Cu 3/2PMo 12O 40 loading and calcination temperature on the catalytic performance was investigated. The optimum Cu 3/2PMo 12O 40 loading was 26%, and the best calcination temperature was 400 ℃. Under the conditions of 175 ℃ and 8 h, the phenol conversion and the transesterification selectivity over 22%Cu 3/2PMo 12O 40/SiO2 calcined at 400 ℃ were 25% and 99.2%, respectively.
