Layered double hydrotalcites pillared by het erop olyoxometates, ZnAl- GeW11Z (Z=Ni2+, Cu2+) and ZnAl-GeW11 have been synhesized by ion exchange. A procedure for intercalating layered double hydroxides is described in...Layered double hydrotalcites pillared by het erop olyoxometates, ZnAl- GeW11Z (Z=Ni2+, Cu2+) and ZnAl-GeW11 have been synhesized by ion exchange. A procedure for intercalating layered double hydroxides is described in this paper, powder X-ray diffraction and IR spectra measuremnts confirm that for GeW11O39Z (H2O)6- and GeW11O8-39intercalation takes place and the gallery heights are of 9.9A. The new compounds are found to be calalytically efficient for the esterification of acetic acid with n-butanol in liquld-phase.展开更多
对不同来源的脂肪酶进行了系统的筛选,并根据位置专一性的差别将脂肪酶分为1,3 特异的、1,3 选择性和非选择性的3类.采用LipozymeRMIM在无溶剂系统中催化甘油、脂肪酸合成1,3 sn 甘油二酯.研究表明脂肪酸、底物醇种类、温度、水分活度对...对不同来源的脂肪酶进行了系统的筛选,并根据位置专一性的差别将脂肪酶分为1,3 特异的、1,3 选择性和非选择性的3类.采用LipozymeRMIM在无溶剂系统中催化甘油、脂肪酸合成1,3 sn 甘油二酯.研究表明脂肪酸、底物醇种类、温度、水分活度对LipozymeRMIM的活力有明显的影响.展开更多
以L aC l3.7H2O替代传统液体无机酸为催化剂,以合成异丁酸正丁酯为探针反应考察催化酯化反应的优化条件,并在此条件下合成了多种异丁酸酯,比较了不同催化剂对催化合成异丁酸正丁酯的影响。实验结果表明,L aC l3.7H2O对酯化反应具有良好...以L aC l3.7H2O替代传统液体无机酸为催化剂,以合成异丁酸正丁酯为探针反应考察催化酯化反应的优化条件,并在此条件下合成了多种异丁酸酯,比较了不同催化剂对催化合成异丁酸正丁酯的影响。实验结果表明,L aC l3.7H2O对酯化反应具有良好的催化活性,并能避免液体无机酸催化剂所引起的弊端,异丁酸正丁酯的酯化率可达96.5%。且催化剂易回收,反应后处理简单,无废酸排放,是一种环境友好型催化剂。展开更多
The infrared spectrum of pyridine adsorbed on surface of ZnSO 4·7H 2O indicates it exhibits Lewis acid centers as a catalyst. Experiments showed that it had good catalytic performance in esterification of oxalic ...The infrared spectrum of pyridine adsorbed on surface of ZnSO 4·7H 2O indicates it exhibits Lewis acid centers as a catalyst. Experiments showed that it had good catalytic performance in esterification of oxalic acid with iso-amyl alcohol with ester yield being 97.5% in following conditions: the molar ratio of isoamyl alcohol to oxalic acid 2.8, catalyst amount 7.4%(based on the mass of oxalic acid), reaction temperature 145 ℃, reaction time 1.5 h. The catalyst could be used repeatedly for six times.展开更多
Methane sulfonate of copper, cobalt, zinc, lanthanide, praseodymium and neodymium are synthesized and characterized by FTIR and TGA. Methane sulfonates are used as the catalysts in the esterification of chloroacetic a...Methane sulfonate of copper, cobalt, zinc, lanthanide, praseodymium and neodymium are synthesized and characterized by FTIR and TGA. Methane sulfonates are used as the catalysts in the esterification of chloroacetic acid with isopropanol. Catalytic activity of methane sulfonates is studied and compared with other Lewis acids. Under the condition of 1.2/1 molar ratio of isopropanol to chloroacetic acid, 1% catalyst (molar percent of chloroacetic acid), 2.5h reaction time, 80～ 85℃ temperature and benzene as water carrying agent. The experimental results showed that catalytic activity of Lanthanide methane sulfonate was the best, the yield of isopropyl chloroacetate reaches 88.7% . Copper methane sulfonate can be reused for three times without distinct loss of catalytic activity.展开更多
文摘Layered double hydrotalcites pillared by het erop olyoxometates, ZnAl- GeW11Z (Z=Ni2+, Cu2+) and ZnAl-GeW11 have been synhesized by ion exchange. A procedure for intercalating layered double hydroxides is described in this paper, powder X-ray diffraction and IR spectra measuremnts confirm that for GeW11O39Z (H2O)6- and GeW11O8-39intercalation takes place and the gallery heights are of 9.9A. The new compounds are found to be calalytically efficient for the esterification of acetic acid with n-butanol in liquld-phase.
文摘以L aC l3.7H2O替代传统液体无机酸为催化剂,以合成异丁酸正丁酯为探针反应考察催化酯化反应的优化条件,并在此条件下合成了多种异丁酸酯,比较了不同催化剂对催化合成异丁酸正丁酯的影响。实验结果表明,L aC l3.7H2O对酯化反应具有良好的催化活性,并能避免液体无机酸催化剂所引起的弊端,异丁酸正丁酯的酯化率可达96.5%。且催化剂易回收,反应后处理简单,无废酸排放,是一种环境友好型催化剂。
文摘The infrared spectrum of pyridine adsorbed on surface of ZnSO 4·7H 2O indicates it exhibits Lewis acid centers as a catalyst. Experiments showed that it had good catalytic performance in esterification of oxalic acid with iso-amyl alcohol with ester yield being 97.5% in following conditions: the molar ratio of isoamyl alcohol to oxalic acid 2.8, catalyst amount 7.4%(based on the mass of oxalic acid), reaction temperature 145 ℃, reaction time 1.5 h. The catalyst could be used repeatedly for six times.
文摘Methane sulfonate of copper, cobalt, zinc, lanthanide, praseodymium and neodymium are synthesized and characterized by FTIR and TGA. Methane sulfonates are used as the catalysts in the esterification of chloroacetic acid with isopropanol. Catalytic activity of methane sulfonates is studied and compared with other Lewis acids. Under the condition of 1.2/1 molar ratio of isopropanol to chloroacetic acid, 1% catalyst (molar percent of chloroacetic acid), 2.5h reaction time, 80～ 85℃ temperature and benzene as water carrying agent. The experimental results showed that catalytic activity of Lanthanide methane sulfonate was the best, the yield of isopropyl chloroacetate reaches 88.7% . Copper methane sulfonate can be reused for three times without distinct loss of catalytic activity.
