H6P2W18O62/KH570-SiO2催化剂的制备、表征及催化合成乙酸正丁酯  

Preparation,characterization and catalytic synthesis ofn-butyl acetate with H6P2W18O62/KH570-SiO2

作　　者：曹小华[1,2] 钟婵娟 穆晶[1] 谢宝华 徐常龙[1,2] 占昌朝 CAO Xiaohua;ZHONG Chanjuan;MU Jing;XIE Baohua;XU Changlong;ZHAN Changchao(College of Chemical and Environmental Engineering, Jiujiang University, Jiujiang 332005, China;Jiangxi Provincial Engineering Research Center of Ecological Chemical Industry, Jiujiang 332005, China)

机构地区：[1]九江学院化学与环境工程学院,江西九江332005 [2]江西省生态化工工程技术研究中心,江西九江332005

出　　处：《功能材料》2020年第8期8117-8122,共6页Journal of Functional Materials

基　　金：国家自然科学基金资助项目(21864015,51562016,21861022);江西省自然科学基金资助项目(20171BAB206015);江西省教育厅科技资助项目(GJJ180892,GJJ180896,GJJ190896);2019年国家级大学生创新创业训练计划资助项目(201911843018)。

摘　　要：以硅烷偶联剂KH570改性SiO2为载体,利用浸渍法制备负载型Dawson结构磷钨酸催化剂H6P2W18O62/KH570-SiO2,并对其进行FT-IR、SEM、EDS及BET等表征。以H6P2W18O62/KH570-SiO2为催化剂催化合成乙酸正丁酯,探究了催化剂用量、醇酸摩尔比、反应温度及时间对酯化率的影响。FT-IR及EDS表征结果表明,负载后磷钨酸仍然保持着Dawson结构。SEM表征结果表明,H6P2W18O62均匀分散在KH570-SiO2上。BET测试结果表明,负载型H6P2W18O62/KH570-SiO2催化剂比表面积(122.40 m^2/g)远大于H6P2W18O62分比表面积(1.75 m^2/g)。H6P2W18O62/KH570-SiO2是催化合成乙酸正丁酯的有效催化剂,当催化剂用量为1.9%(占反应原料总质量的百分数)、反应温度为120℃、醇酸比为2∶1、反应时间为2 h时,酯化率最高达96.4%。当催化剂重复利用5次后,酯化率仍能达到88.2%。The supported Dawson structure phosphotungstic acid catalyst H6P2W18O62/KH570-SiO2 was prepared by impregnation method with SiO2 modified with silane coupling agent KH570 as the carrier,and characterized by FT-IR,EDS,SEM and BET.A new method of synthesis of n-butyl acetate catalyzed by H6P2W18O62/KH570-SiO2 has been studied.The main factors,including quantity of the catalyst,molar ratio of reactants,reaction temperature and reaction time were investigated.FT-IR and EDS characterization results showed that phosphotungstic acid still maintained Dawson structure after loading.SEM characterization results showed that H6P2W18O62 was uniformly dispersed on KH570-SiO2.BET test results showed that the specific surface area of H6P2W18O62/KH570-SiO2(122.40 m^2/g)was much larger than that of H6P2W18O62(1.75 m^2/g).The experimental results show that H6P2W18O62/KH570-SiO2 was an effective catalyst for the synthesis of n-butyl acetate.When the mass ratio of the catalyst to total reactant was 1.9%,the reaction time was 2 h,the molar ratio of n-butyl alcohol to acetic acid was 2:1 and the reaction temperature was 120℃,the highest esterification rate was 96.4%.The catalyst could be reused for 5 times and the isolated of n-butyl acetate was still above 88.2%under the optimal conditions.

关 键 词：Dawson结构磷钨酸 二氧化硅 KH570 负载型催化剂 乙酸正丁酯 

分 类 号：TQ426.91[化学工程]