硅藻土负载Dawson结构磷钨酸催化合成对羟基苯甲酸正丁酯  

Synthesis of Butyl p-Hydroxybenzoate over Diatomite Supported Phosphotungstic Acid with Dawson Structure

作　　者：曹小华[1,2] 任杰[1] 柳闽生[3] 占昌朝[1,2] 严平[2] 

机构地区：[1]浙江工业大学化学工程与材料学院,浙江杭州310014 [2]九江学院化学与环境工程学院,江西九江332005 [3]南京晓庄学院生物化工与环境工程学院,江苏南京211171

出　　处：《石油化工》2013年第2期191-197,共7页Petrochemical Technology

基　　金：国家自然科学基金项目(21161009);江西省自然科学基金项目(20122BAB213001;20114BAB213002);江西省教育厅科技资助项目(GJJ10626;GJJ11613)

摘　　要：以硅藻土为载体,采用浸渍法制备了H6P2W18O62/硅藻土催化剂,并采用FTIR,EDS,XRD,SEM等手段对催化剂进行了表征;以对羟基苯甲酸正丁酯的合成反应为探针,考察了H6P2W18O62/硅藻土催化剂的性能;通过单因次和正交实验研究了H6P2W18O62负载量、催化剂用量、正丁醇与对羟基苯甲酸的摩尔比(醇酸比)、反应时间和反应温度对酯化反应的影响。确定了优化工艺条件为:H6P2W18O62负载量为40%(基于硅藻土的质量)、催化剂用量0.5 g(占反应体系总质量的2.8%)、醇酸比3、反应时间3.0 h、反应温度125℃。在此条件下,对羟基苯甲酸正丁酯的平均收率可达90.8%;催化重复使用5次,对羟基苯甲酸正丁酯收率仍可达65.6%。Diatomite supported phosphotungstic acids with Dawson structure were prepared by an impregnation method and used as catalysts for the synthesis of butyl p-hydroxybenzoate by the esterification ofp-hydroxy benzoic acid with n-butyl alcohol. The effects of the catalyst preparation and reaction conditions on the esterification were investigated through orthogonal experiments. The yield of butyl p-hydroxybenzoate could reach 90.8% under the optimum conditions of phosphotungstic acid loading on the diatomite support 40%（based on the diatomite mass）, mass ratio of the catalyst to the total reactants 2.8%, molar ratio of n-butyl alcohol to p-hydroxy benzoic acid 3, reaction time 3.0 h and reaction temperature 125 ℃. The catalyst could be reused for 5 times and the yield of butyl p-hydroxybenzoate was still kept at 65.6%.

关 键 词：硅藻土 Dawson结构磷钨酸 对羟基苯甲酸正丁酯 酯化反应 

分 类 号：TQ424.22[化学工程]