以MCM-48为载体,通过浸渍法制备了H6P2W18O62/MCM-48催化剂,并采用FT-IR、XRD、SEM、EDS对催化剂进行表征。以微波促进30%(质量分数)H2O2氧化环己酮合成己二酸反应为探针,考察了H6P2W18O62/MCM-48的催化性能,并通过正交实验确定了优化的工艺条件。结果表明,采用H6P2W18O62负载量40%的H6P2W18O62/MCM-48催化剂,在优化的合成己二酸的工艺条件下,即催化剂质量分数(以环己酮质量计)5.1%、n(C6H10O)∶n(H2O2)∶n(H2C2O4·2H2O) = 100∶450∶1.88、反应温度95℃、微波功率300 W、反应时间3.5 h,己二酸收率可达81.3%;催化剂重复使用5次,己二酸收率仍可达到64.6%。
Dawson structure phosphotungstic acid supported on MCM-48 was prepared by impregnation method and characterized by FT-IR, XRD, SEM and EDS. The synthesis of adipic acid with cyclohexanone and 30% hydrogen peroxide under microwave irradiation was carried out as a probe reaction to study the catalytic activity of H6P2W18O62/MCM-48.The main reaction conditions were optimized with orthogonal experiments. The results showed that with 40% H6P2W18O62/MCM-48 as catalyst, under the optimal conditions of the catalyst to cyclohexanone mass ratio of 5.1%, n(C6H10O)∶n(H2O2)∶ n(H2C2O4·2H2O)=100∶450∶1.88, the reaction temperature of 95℃, microwave power of 300 W, irradiation time of 3.5 h, the isolated yield of adipic acid could reach 81.3%, and the catalyst could be reused five times with the isolated yield of adipic acid still above 64.6%.