铜基甲醇合成催化剂的TPR研究

TPR study on copper-based methanol synthesis catalysts

采用并流共沉淀法制备了一系列具有不同Cu/Zn的甲醇合成催化剂。通过活性测试可知 ,并流法所制备的催化剂最佳Cu/Zn大约为 5 / 4。催化剂TPR研究表明 ,当铝含量固定时 ,具有最佳Cu/Zn(即 5 / 4 )的铜基催化剂 ,其主还原温度最低。考察了在不同 pH值时进行并流共沉淀所制备的催化剂的TPR ,表明沉淀时的 pH值对催化剂的结构有很大影响 ,并对其本质原因进行了深入探讨。另外 ,考察了铝含量对催化剂还原行为的影响以及在不同升温速率下催化剂TPR的差异。

A series of copper based catalysts with different Cu/Zn ratio(mole) were prepared by one step parallel flow co precipitation. The activity test showed that the optimum Cu/Zn ratio was around 1.25. TPR results of the catalysts showed that when aluminum content is fixed, the catalyst sample with the optimum Cu/Zn ratio has the lowest reduction temperature. The TPR results of the catalyst samples prepared at different pH values showed that the structure of copper based catalyst is greatly affected by pH values in the precipitation process. The causes behind this were discussed in detail. Effect of aluminum content on reduction behaviour of copper based catalyst was also investigated. TPR results at different rate of heating were compared.