稀土镧、铈对Cu/ZnO/Al_2O_3催化剂水汽变换性能的影响

以稀土镧和铈为助剂、聚氧乙烯十二烷基醚为表面活性剂采用共沉淀法制备催化剂Cu/ZnO/Al2O3,利用微型反应装置评价了催化剂的活性,并应用TPD、TPR等技术对催化剂吸附性能、还原性能进行表征。结果表明,镧添加剂的促进效果比铈好。助剂的添加使催化剂表面活性中心增多,活性组分电荷密度增大,从而提高了催化剂的活性。

Effects of Rare Earths on the Performances of Cu/ZnO/Al2O3 Catalysts for Water-gas Shift Reaction

The Cu/ZnO/Al2O3 catalysts were prepared by co-precipitation, using rare earth lanthanun or cerium as promoters and polyoxyethylene-dodecyl-ether as surfactant. The catalytic activity of the catalysts were evaluated by a continuous micro reactor and the phase structure, adsorption and reduction properties of the catalysts were studied by TPD and TPR techniques. The results showed that lanthanun exhibited better promotion behavior than cerium. Adding rare earth promoters to the Cu/ZnO/Al2O3 catalyst can increase the active sites of the catalyst surface and the electronic cloud density of the active components, so enhance the activity of the catalysts.