Microporous heteropolyoxometalates Cs\-\%x\%H\-\{5-\%x\%\}PW\-\{10\}V\-2O\-\{40\}/SiO\-2 were synthesized by a sol\|gel technique and characterized by IR, UV\|Vis, BET adsorption/desorption isotherm. The structural fr...Microporous heteropolyoxometalates Cs\-\%x\%H\-\{5-\%x\%\}PW\-\{10\}V\-2O\-\{40\}/SiO\-2 were synthesized by a sol\|gel technique and characterized by IR, UV\|Vis, BET adsorption/desorption isotherm. The structural frameworks of Cs\-\%x\%H\-\{5-\%x\%\}PW\-\{10\}V\-2O\-\{40\} are preserved within the silica networks. Cs\-\%x\%H\-\{5-\%x\%\}PW\-\{10\}V\-2O\-\{40\}/SiO\-2 are a kind of polyoxometalate\|silica gel hybrids with uniform micropores of ca. 0.65 nm. They show a high catalytic activity for oxidation reaction of benzyl alcohol by H\-2O\-2(30%) in liquid\|solid systems and product selectivity for benzaldehyde(>96%). The highest activity is observed at \%x\%=2.5 in Cs\-\%x\%H\-\{5-\%x\%\}PW\-\{10\}V\-2O\-\{40\}/SiO\-2 and little formation of benzoic acid and a more deeply oxidized product is observed.展开更多
Pd and /or Cu - La2O3/SiO2 catalysts were prepared by Pd and/or Cu supported on La2O3/SiO2 with impregnation The capacities of catalysts reduction and the performance of reaction were studied by H2-TPR and hydrogenati...Pd and /or Cu - La2O3/SiO2 catalysts were prepared by Pd and/or Cu supported on La2O3/SiO2 with impregnation The capacities of catalysts reduction and the performance of reaction were studied by H2-TPR and hydrogenation of CO2 The results of H2-TPR indicate that increasing the content of CuO is advantageous to the reduction of high dispersing CuO, but adding La2O3 hinder the reduction of high dispersing CuO It was found that Pd-Cu alloy formed while Pd, Cu impregnated on La2O3/SiO2 The results of hydrogenation of CO2 indicate that CO2 conversion is promoted by adding La2O3 increasing the content of CuO The thermal stablity of methanol formation was improved by adding La2O3 Aldehyde can be obtained when Pd-Cu were used as active components, and the production of methanol was related to the content of Pd loaded on the展开更多
文摘Microporous heteropolyoxometalates Cs\-\%x\%H\-\{5-\%x\%\}PW\-\{10\}V\-2O\-\{40\}/SiO\-2 were synthesized by a sol\|gel technique and characterized by IR, UV\|Vis, BET adsorption/desorption isotherm. The structural frameworks of Cs\-\%x\%H\-\{5-\%x\%\}PW\-\{10\}V\-2O\-\{40\} are preserved within the silica networks. Cs\-\%x\%H\-\{5-\%x\%\}PW\-\{10\}V\-2O\-\{40\}/SiO\-2 are a kind of polyoxometalate\|silica gel hybrids with uniform micropores of ca. 0.65 nm. They show a high catalytic activity for oxidation reaction of benzyl alcohol by H\-2O\-2(30%) in liquid\|solid systems and product selectivity for benzaldehyde(>96%). The highest activity is observed at \%x\%=2.5 in Cs\-\%x\%H\-\{5-\%x\%\}PW\-\{10\}V\-2O\-\{40\}/SiO\-2 and little formation of benzoic acid and a more deeply oxidized product is observed.
文摘Pd and /or Cu - La2O3/SiO2 catalysts were prepared by Pd and/or Cu supported on La2O3/SiO2 with impregnation The capacities of catalysts reduction and the performance of reaction were studied by H2-TPR and hydrogenation of CO2 The results of H2-TPR indicate that increasing the content of CuO is advantageous to the reduction of high dispersing CuO, but adding La2O3 hinder the reduction of high dispersing CuO It was found that Pd-Cu alloy formed while Pd, Cu impregnated on La2O3/SiO2 The results of hydrogenation of CO2 indicate that CO2 conversion is promoted by adding La2O3 increasing the content of CuO The thermal stablity of methanol formation was improved by adding La2O3 Aldehyde can be obtained when Pd-Cu were used as active components, and the production of methanol was related to the content of Pd loaded on the
