高岭土复合型固体酸催化合成异丁酸丁酯

以质量比为1∶9∶20的硝酸铈铵、高岭土和SnCl4·5H2O制备了高岭土复合型固体酸催化剂,制备条件为70℃水浴中陈化12h,促进剂H2SO4浓度为2.0mol/L,浸渍12h,350℃焙烧3h,并采用XRD对催化剂进行了表征。该催化剂用于异丁酸与正丁醇的酯化反应合成了异丁酸丁酯,考察了带水剂种类、催化剂用量、异丁酸与正丁醇的摩尔比、反应时间及催化剂重复使用性等因素对酯收率的影响。结果表明,该催化剂具有催化活性高、易分离回收、成本低、重复使用性好等优点。适宜反应条件为醇酸摩尔比为1.7、催化剂用量为反应物总质量的2.0%、反应时间100min,酯收率为96.5%。该催化剂重复使用6次,其酯收率仍接近80%。

Synthesis of Butyl-isobutyrate with Composite Kaolin Solid Acid as Catalyst

Butyl-isobutyrate was synthesized from isobutyric acid and n-butanol with a new composite solid acid catalyst.Preparing conditions of the catalyst were：mass ratio of ammonium ceric nitrate to kaolin to SnCl_4·5H_2O 1∶9∶20，ageing time12h at 70℃，concentration of sulfuric acid 2.0mol/L，impregnation time12h，and calcination at 350℃ for 3h.The catalyst was characterized by XRD.As using synthesis of butyl-isobutyrate，effects of type of water entrainer，catalyst dosage，mole ratio of butanol to isobutyric acid and reaction time on the yield of butyl-isobutyrate were all studied.Under the optimal conditions：mole ratio of butanol to isobutyric acid 1.7，reaction time 100 min，and mass fraction of catalyst in all of reaction system 2.0%，the yield is 96.5%.The catalyst also has excellent stability.When it was reused for six times，the yield could approach 80%.The composite solid acid catalyst takes advantages of low cost，highly active，non-polluting and reusable.