A novel solid superacid catalyst S2O8^2-/ZrO2-CeO2 was prepared by a coprecipitation method and characterized by means of XRD FTIR, BET, TEM and DSC/TG analysis methods. The results indicated that incorporation of app...A novel solid superacid catalyst S2O8^2-/ZrO2-CeO2 was prepared by a coprecipitation method and characterized by means of XRD FTIR, BET, TEM and DSC/TG analysis methods. The results indicated that incorporation of appropriate amounts of Ce into the catalyst was beneficial to the formation of sole tetragonal ZrO2 and effectively prevented from the formation of monoclinic ZrO〉 and restrained the loss of sulfated species. XRD revealed the presence of tetragonal Ce0.16Zr0.84O2phase in the case of S2O8^2-/ZrO2-CeO2 calcined above 500 ℃. Catalytic activities of S2O8^2-/ZrO2-CeO2 for the esterification of lactic acid with n-butanol was studied. The results showed that the optimum conditions were as follows： calcination temperature of the catalyst 600 ℃, n（lactic acid）：n（n-butyl alcohol）=1.0：3.0, w（S2O8^2-/ZrO2- CeO2）=12.0%, reaction temperature 145 ℃, and reaction time 2 h. The esterification efficiency of lactic acid was about 96.6%.展开更多
SO 24? /TiO2-La2O3, a novel solid superacid, was prepared and its catalytic activities at different synthetic conditions are discussed with esterification of n-butanoic acid and n-butyl alcohol as probing reaction. Th...SO 24? /TiO2-La2O3, a novel solid superacid, was prepared and its catalytic activities at different synthetic conditions are discussed with esterification of n-butanoic acid and n-butyl alcohol as probing reaction. The optimum conditions have also been found, mole ratio of n(La3+):n(Ti4+) is 1:34, the soaked consistency of H2SO4 is 0.8 mol/L, the soaked time of H2SO4 is 24 h, the calcining temperature is 480 °C, the calcining time is 3 h. Then it was applied in the catalytic synthesis of ten important ketals and acetals as catalyst and revealed high catalytic activity. Under these conditions on which the molar ratio of aldehyde/ketone to glycol is 1:1.5, the mass ratio of the catalyst used in the reactants is 0.5%, and the reaction time is 1.0 h, the yields of ketals and acetals can reach 41.4%～95.8%.展开更多
The synthesis of isoamyl butyrate with isoamyl alcohol and butyric acid as reactants and rare-earth solid superacid SO42-/TiO2/La3+ as catalyst had been studied. The influent actors of reaction were investigated. The ...The synthesis of isoamyl butyrate with isoamyl alcohol and butyric acid as reactants and rare-earth solid superacid SO42-/TiO2/La3+ as catalyst had been studied. The influent actors of reaction were investigated. The results showed that the appropriate conditions should be: Weight of catalyst was 0. 5g (weight of butyric acid if 0. 2mol); molar ratio of isoamyl alcohol to butyric acid was 1. 8: 1; reaction time was 2. 0 h; the taking water reagent (Toluene) was 15mL. The yield of isoamyl butyrate was about 99. 0%.展开更多
The rare-earth solid superacids-SO 2- 4/TiO 2/La 3+ were prepared by precipitation and impregnation and were characterized by IR,XRD and Hammett indicator.The synthesis of ethyl phenylacetate with ethanol and phenylac...The rare-earth solid superacids-SO 2- 4/TiO 2/La 3+ were prepared by precipitation and impregnation and were characterized by IR,XRD and Hammett indicator.The synthesis of ethyl phenylacetate with ethanol and phenylacetic acid as reactants and rare-earth solid superacid SO 2- 4/TiO 2/La 3+ (La 3+ concentration of the soak solution:0 07mol·L -1 ,the calcination temperature:500℃ and the calcination time:3h)as catalyst was studied.The results showed that the appropriate conditions were as follow:mass of catalyst 1 0g(based on 0 05 mole phenylacetic acid),n(ethanol):n(phentlacetic acid)=4 0∶1 0,reaction time 5 0h.The yield of ethyl phenylacetate was about 89 8%.展开更多
基金supported by the Science and Technique Foundation of Shaaxi Province of China (2008K07-32)the Foundation of Shaanxi Educa- tional Committee of China (08JK228)the Graduate Innovation Fund of Shaanxi University of Science and Technology
文摘A novel solid superacid catalyst S2O8^2-/ZrO2-CeO2 was prepared by a coprecipitation method and characterized by means of XRD FTIR, BET, TEM and DSC/TG analysis methods. The results indicated that incorporation of appropriate amounts of Ce into the catalyst was beneficial to the formation of sole tetragonal ZrO2 and effectively prevented from the formation of monoclinic ZrO〉 and restrained the loss of sulfated species. XRD revealed the presence of tetragonal Ce0.16Zr0.84O2phase in the case of S2O8^2-/ZrO2-CeO2 calcined above 500 ℃. Catalytic activities of S2O8^2-/ZrO2-CeO2 for the esterification of lactic acid with n-butanol was studied. The results showed that the optimum conditions were as follows： calcination temperature of the catalyst 600 ℃, n（lactic acid）：n（n-butyl alcohol）=1.0：3.0, w（S2O8^2-/ZrO2- CeO2）=12.0%, reaction temperature 145 ℃, and reaction time 2 h. The esterification efficiency of lactic acid was about 96.6%.
基金Project supported by the National Natural Science Foundation of China (No. 20471044), and the Natural Science Foundation of Hubei Province (No. 2005ABA053), China
文摘SO 24? /TiO2-La2O3, a novel solid superacid, was prepared and its catalytic activities at different synthetic conditions are discussed with esterification of n-butanoic acid and n-butyl alcohol as probing reaction. The optimum conditions have also been found, mole ratio of n(La3+):n(Ti4+) is 1:34, the soaked consistency of H2SO4 is 0.8 mol/L, the soaked time of H2SO4 is 24 h, the calcining temperature is 480 °C, the calcining time is 3 h. Then it was applied in the catalytic synthesis of ten important ketals and acetals as catalyst and revealed high catalytic activity. Under these conditions on which the molar ratio of aldehyde/ketone to glycol is 1:1.5, the mass ratio of the catalyst used in the reactants is 0.5%, and the reaction time is 1.0 h, the yields of ketals and acetals can reach 41.4%～95.8%.
文摘The synthesis of isoamyl butyrate with isoamyl alcohol and butyric acid as reactants and rare-earth solid superacid SO42-/TiO2/La3+ as catalyst had been studied. The influent actors of reaction were investigated. The results showed that the appropriate conditions should be: Weight of catalyst was 0. 5g (weight of butyric acid if 0. 2mol); molar ratio of isoamyl alcohol to butyric acid was 1. 8: 1; reaction time was 2. 0 h; the taking water reagent (Toluene) was 15mL. The yield of isoamyl butyrate was about 99. 0%.
文摘The rare-earth solid superacids-SO 2- 4/TiO 2/La 3+ were prepared by precipitation and impregnation and were characterized by IR,XRD and Hammett indicator.The synthesis of ethyl phenylacetate with ethanol and phenylacetic acid as reactants and rare-earth solid superacid SO 2- 4/TiO 2/La 3+ (La 3+ concentration of the soak solution:0 07mol·L -1 ,the calcination temperature:500℃ and the calcination time:3h)as catalyst was studied.The results showed that the appropriate conditions were as follow:mass of catalyst 1 0g(based on 0 05 mole phenylacetic acid),n(ethanol):n(phentlacetic acid)=4 0∶1 0,reaction time 5 0h.The yield of ethyl phenylacetate was about 89 8%.
