低负载量Ru/Al2O3催化剂上对苯二甲酸二甲酯加氢制1,4-环己烷二甲酸二甲酯活性研究

Activity of dimethyl terephthalate hydrogenation to dimethyl 1,4-cyclohexanedicarboxylate over low load Ru/AlO catalyst

采用浸渍法制备了一种较低Ru负载量(质量分数为0.55%)的Ru/Al2O3催化剂,在固定床中评价了其作用下对苯二甲酸二甲酯(DMT)加氢制1,4-环己烷二甲酸二甲酯(DMCD)的反应活性,考察了不同焙烧温度对Ru/Al2O3催化剂催化加氢活性的影响。结果表明,催化加氢过程中,相较于未经焙烧的催化剂,经200℃和350℃焙烧的催化剂稳定性和DMT转化率下降,而DMCD选择性升高。XRD和BET分析表明,催化剂表面活性物质Ru数目减少是引起催化剂失活的原因之一。

A Ru/Al2O3 catalyst with low Ru load(mass fraction 0.55%) was prepared by impregnation method and the catalytic hydrogenation activity of the catalyst for dimethyl terephthalate(DMT) to dimethyl 1,4-cyclohexanedicarboxylate(DMCD) was evaluated in a fixed bed reactor. The effect of calcination temperature on the catalytic activity of Ru/Al2O3 catalyst was investigated.The results showed that, compared with non-calcined catalyst, the stability and DMT conversion of the catalysts calcined at 200 ℃ and 350 ℃ decreased, while the selectivity of DMCD increased in the process of catalytic hydrogenation. XRD and BET analysis showed that the decrease of surface active species Ru was one of the reasons for the catalyst deactivation.