A study on the sulfur-resistant catalysts for water gas shift reaction III. Modification of Mo/gamma-Al2O3 catalyst with iron group metals

Mo/gamma -Al2O3 catalysts modified with Fe, Co, and Ni were prepared by imp regnation method and catalytic activity for water gas shift reaction was ex amined. The optimum amount of Mo loaded for the reaction was 10 wt% MoO3 to gamma -Al2O3. The catalytic activity of MoO3/gamma -Al2O3 was increased by modifying with Fe, Co, and Ni in the order of Co approximate to Ni > Fe. T he optimum amounts of Co and Ni added were 3 wt% based on CoO and NiO to 10 wt% MoO3/gamma -Al2O3, respectively. The TPR (temperature-programmed reduc tion) analysis revealed that the addition of Co and Ni enhanced the reducib ility of the catalysts. The results of both catalytic activity and TPR expe riments strongly suggest that the redox property of the catalyst is an impo rtant factor in water gas shift reaction on the sulfided Mo catalysts, whic h could be an evidence of oxy-sulfide redox mechanism.