Abstract: The reduction and passivation behaviour of low pressure methanol CuO-ZnO-Al2O3-V2O5, catalysts have been studied with thermal analysis technique. along with XRD, IR, SEM and activity evaluation. Results show that the industrial catalyst contains about 25% basic carbonate, which is beneficial for getting better selectivity, activity and stability. Catalysts precalcined at 350℃ will lead to the formation of unfavourable structure. Direct reduction of industrial catalysts at low H2 concentration with high gas flow rate and at low temperature cascade rising rate will give good thermal stability and catalytic activity. It is attributed to the fact that some carbonate and hydroxyl groups are retained in the structure. They are assumed to be the necessary coordination species to form active sites, while the precalcined catalysts have lost most of these functional groups. Catalyst passivated under extremely low O2 concentration (0.01%)can restore its activity almost completely after re-reduction. A mathematical model of reduction kinetics has been set up from the thermo-gravimetric curve.

摘要： 本文研究了CuO-ZnO-Al_2O_3-V_2O_5低压合成甲醇催化剂的还原及钝化.结果表明:工业催化剂含约25%的碱式碳酸盐,它对活性与稳定性有良好作用.使用前如先经623K煅烧则将破坏此有利结构.将工业催化剂直接采用低氢浓度、高空速和低升温速率的阶梯式提温方式还原,可提高活性及选择性.用含氧浓度极低的氮气钝化,经再还原可基本恢复活性.本文还提出了还原过程的动力学方程.