Al改性Cu/SiO_(2)催化剂催化二甘醇脱氢制对二氧环己酮的研究

Study on Al-modified Cu/SiO_(2) catalysts for dehydrogenation of diethylene glycol to para-dioxanone

通过共沉淀法对Al改性Cu/SiO_(2)催化剂进行研究,并利用XRD、BET、TEM、ICP等对催化剂进行表征。同时对催化剂进行二甘醇(DEG)制备对二氧环己酮(PDO)脱氢性能评价,并对催化剂的制备工艺和脱氢反应工艺条件进行了优化。结果表明,在共沉淀反应温度为80℃、搅拌速度为300 r/min、焙烧温度为400℃、焙烧时间为2 h、脱氢反应温度为250℃、常压、DEG液时空速为0.4 h^(-1)、氢气空速为240 h^(-1)的条件下,DEG转化率达97.2%,PDO选择性达96.4%。在最佳条件下催化剂连续反应1440 h后,DEG转化率和PDO选择性均在95%以上,催化剂的稳定性较好。

Al-modified Cu/SiO_(2) catalysts are studied through co-precipitation method,and characterized by means of XRD,BET,TEM,and ICP.The dehydrogenation performance of catalysts are evaluated in the preparation of para-dioxanone(PDO)from diethylene glycol(DEG).The preparation process and dehydrogenation reaction conditions for the catalysts are optimized.The results show that the conversion rate of DEG reaches 97.2%and the selectivity of PDO reaches 96.4%when the co-precipitation reaction temperature is 80℃,the stirring speed is 300 r·min^(-1),the calcination temperature 400℃,the calcination time 2 h,the dehydrogenation reaction temperature 250℃,under normal pressure,the liquid space velocity of DEG 0.4 h^(-1) and the space velocity of hydrogen 240 h^(-1).The conversion rate of DEG and the selectivity of PDO are both above 95%after the reaction has performed continuously over the catalyst for 1440 h under the optimal conditions.The catalyst has a good stability.