【摘要】 报道了合成乳酸酯的新方法，即以乳酸和醇为原料，在对甲苯磺酸催化下以氧化钙为脱水剂，采用索氏提取器进行回流脱水合成乳酸酯．应用该方法，酯化反应时间缩短到３ｈ，收率高达８１％～９８％．同时对影响收率诸因素进行了考察，最佳反应条件为乳酸醇对甲苯磺酸的摩尔比为２４２０１更多还原

【Abstract】 La(NO 3) 3 ·6H 2O (or (NH 4) 2Ce(NO 3) 6) and Al(NO 3) 3·9H 2O according to the stoichiometric amounts were dissolved respectively in ammonium oxalate solution,followed by drying to obtain the solid products.The products were powdered and pressed into pellets and then calcined at 600 ℃ and 700 ℃, respectively, resulting in LaAlO 3 and CeAlO 3 compounds with the perovskite structure. X ray and DSC analysis of the La precursor showed that the process of from the drying and decomposing of the precursor, via the formation of the intermediate phase, to the transformation to LaAlO 3 phase was complex. The application of so called soft chemistry method markedly decreased temperatures for the solid state reaction of the perovskite type oxides.更多还原