摘要
通过浸渍法制备了SO42--TiO2/Al2O3固体超强酸催化剂,用Hammett指示剂法测定了其酸强度;以乙酰乙酸乙酯和乙二醇、1,2-丙二醇为原料,合成了苹果酯-A和苹果酯-B,考察了催化剂的焙烧温度、TiO2的负载量、反应温度、反应物配比、催化剂用量等因素对反应的影响以及催化剂的重复使用性。结果表明,在425～575℃温度范围内,SO42--TiO2/Al2O3体系可以形成超强酸;在苹果酯-A和苹果酯-B合成中具有催化活性高、催化速率快、化学稳定性好,重复使用性佳、无环境污染;在最佳条件下,苹果酯-A和苹果酯-B的收率分别可达89.3％和91.5％,质量分数为97％～99％。
SO42- -TiO2/Al2O3 solid superacidiccatalyst was prepared by impregnation process.The acidic strength was determined by Hammett indicator method. Adopting SO42- -TiO2/Al2O3 solid superacid as catalyst. Malate A and malate B were synthesired by acetyl acetic ether, di-ethylene glycol and 1,2 propanediol. We have investigated the effect of calcination temperature, blending ratio of the reactants, amount of catalyst and so on factors on the reaction and the repeatability of the catalyst.The results showed within the temperature range 425 to 575 ℃, SO42--TiO2/Al2O3 system can form super strong acid. SO4-2-TiO2/Al2O3 solid superacid possesses high catalytic activity and rate,good chemical stability, good repeatability and no enviromental pollution produced. In optimum conditions, the yields of malate-A and malate-B can reach 89.3 % and 91.5 % , respectively. The molefraction is 97 % to 99 % .
出处
《当代化工》
CAS
2003年第1期9-11,59,共4页
Contemporary Chemical Industry
