摘要
制备了以Ga2(SO4)3为活性组分、SnO2-高岭土为复合载体的酯化催化剂Ga2(SO4)3/SnO2-高岭土,利用IR、XRD测试技术表征了催化剂的物化性质;并将该催化剂用于乳酸与正丁醇进行酯化反应合成了乳酸丁酯,考察了催化剂制备条件(浸渍时间和焙烧时间)、催化剂用量、n(正丁醇)∶n(乳酸)、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,该催化剂催化活性高、成本低、制备方法简单并且易分离回收。催化剂的适宜制备条件是SnCl4.5H2O和高岭土的质量比1∶3、饱和Ga2(SO4)3溶液浸渍4 h、300℃焙烧2 h。该催化剂催化合成乳酸丁酯的适宜反应条件为:n(正丁醇)∶n(乳酸)=1.6、催化剂用量为反应物总质量的2.5%、反应时间3.5h。在此条件下,酯收率为95.3%。催化剂使用4次后,酯收率仍可达90%以上。
A novel supported sulphate Ga_2（SO_4）_3/SnO_2-kaolin catalyst was prepared and characterized by using IR and XRD methods.The suitable preparing conditions of the catalyst were： 1∶3 mass ratio of SnCl_4·5H_2O to kaolin,impregnation time of 4 h in Ga_2（SO_4）_3 saturated aqueous solution and calcination at 300 ℃ for 2 h. Then butyl lactate was synthesized from n-butanol and lactic acid by using that supported sulphate Ga2（SO4）3/SnO2-kaolin as the catalyst.Effects of catalyst dosage, mole ratio of n-butanol to lactic acid and reaction time on the yield of butyl lactate were examined.Under the optimized reaction conditions,i.e.n（n-butanol）∶n（lactic acid）=1.6,reaction time=3.5 h,and mass fraction of catalyst in total mass of reactants=2.5%,the yield of butyl lactate is 95.3%.Comparing with multicomposite solid acid and acidizing clay,the catalyst possesses advantages of highly active,low cost,easy to be prepared and to be separated from the reaction system.It also can be reused to a certain extent.After the catalyst was used for four times,the yield of butyl lactate could be above 90%.
出处
《化学世界》
CAS
CSCD
北大核心
2010年第12期737-740,共4页
Chemical World
基金
河南省科技厅2009年科技发展计划项目(092102210171)
河南省教育厅自然科学研究计划项目(2008A150002)
