【摘要】 采用浸渍法制备了蒙脱石负载铝基固体酸(SO₄^2-/Al-O-MMT),用FTIR、XRD、TG/DSC、SEM、BET和PyFTIR对其结构进行表征与分析。以乙酸-正丁醇、柠檬酸-正丁醇的酯化反应为探针,研究了焙烧温度、浸渍液浓度对SO₄^2-/Al-O-MMT固体酸催化性能的影响,并测定SO₄^2-/Al-O-MMT固体酸的重复使用性。结果表明:蒙脱石负载铝基固体酸大大地提高了其催化活性。当焙烧温度为400℃,浸渍液浓度为0.75 mol/L时,SO₄^2-/Al-OMMT固体酸表现出最佳的催化活性,其催化合成乙酸正丁酯和柠檬酸三丁酯的酯化率分别可达到99.7%和96.1%。同时,SO₄^2-/Al-O-MMT固体酸表现出较好的重复使用稳定性,重复使用6次后,对于上述两个反应的酯化率分别保持在89.0%和84.6%。更多还原

【Abstract】 Al-based solid acid catalysts supported on montmorillonite( SO₄^2-/ Al-O-MMT) were prepared by impregnation method. The resulting catalysts were characterized by means of FTIR,XRD,TG / DSC,SEM,BET and Py-FTIR analysis methods. The esterification reactions of acetic acid with nbutanol and citric acid with n-butanol were used as probe reactions to investigate the catalytic performance. The effects of calcination temperature and impregnation concentration on catalytic properties were optimized in details,and the catalytic use of SO₄^2-/ Al-O-MMT was measured as well.The experimental results show that the catalytic activity of Al-based solid acid catalysts supported on montmorillonite is greatly improved. The catalyst shows optimal catalytic activities with 99. 7%conversion of acetic acid and 96. 1% conversion of citric acid when the optimal conditions for catalyst preparation are a calcination temperature of 400 ℃ and an impregnation concentration of 0. 75 mol / L.Moreover,the SO₄^2-/ Al-O-MMT solid acid catalyst maintains high activities with 89. 0% conversion of acetic acid and 84. 6% conversion of citric acid after being used for six times,and which indicates that the SO₄^2-/ Al-O-MMT solid acid catalyst exhibits great stability.更多还原