SBA-15分子筛负载磷钨酸催化合成己二酸

Catalytic synthesis of adipic acid over phosphotungstic heterrpoly acid supported on SBA-15

采用SBA-15分子筛等体积浸渍负载磷钨杂多酸制备了PW/SBA-15催化剂,应用XRD、DSG-TGA等对催化剂结构进行分析和表征。结果表明,SBA-15分子筛在负载磷钨酸后,磷钨杂多酸完全引入到SBA-15分子筛的骨架结构中,其稳定性大幅增加。同时采用“一锅煮”的方法用过氧化氢氧化环己烯制得己二酸,运用正交试验法和单因素实验法对催化剂性能进行评价。结果表明,催化剂用量1.75 g、反应时间9 h、反应温度80℃、n(H2O2)∶n(环己烯)=5.47∶1,反应开始加入13.75 mL的H2O2,4 h后再加入13.75 mL的H2O2条件下合成的己二酸收率和纯度最高。

PW/SBA-15 catalyst was prepared by equal volume impregnation of phosphotungstic heterrpoly acid on SBA-15 molecular sieve.Catalyst structure was characterized by means of XRD and DSG-TGA.It was indicated that after the loading of phosphotungstic acid on SBA-15 molecular sieve,the phosphotungstic heteropoly acid was completely introduced into the skeleton structure of SBA-15 molecular sieve,and its stability was greatly increased.Green synthesis of adipic acid from cyclohexene and hydrogen peroxide was carried out by a“one-pot”method.The performance of the catalyst was evaluated by the orthogonal experiments method and the single factor test method.The results showed that yield and purity of the synthesized adipic acid were highest when the amount of catalyst was 1.75 g,reaction time was 9 h,reaction temperature was 80℃,n(H2O2)∶n(cyclohexene)=5.47∶1,initial addition of was 13.75 mL H2O2,and adding another 13.75 mL H2O2 after 4 h of reaction.