Pt/Al2O3 catalysts for benzene hydrogenation

A number of platinum based catalysts were prepared on gamma alumina supports with a view to investigate the effect of the presence of chloride and other preparation variables on the performance. The catalyst samples were evaluated for vapour phase benzene hydrogenation activity and dispersity at room temperature towards hydrogen and carbon monoxide chemisorption. Wet reduction of the catalyst using sodium borohydride was found to be effective for the removal of chloride from the catalyst. Chloride free catalyst prepared with or without sodium borohydride reduction showed better performance than those containing high level of chloride impurity. It was also observed that the activity and dispersity were high for the catalyst reduced with sodium borohydride in comparison to those prepared by direct drying, washing and calcination after impregnation. Promoting effect of sodium borohydride reduced catalyst could be attributed to the removal of chloride ion and also to the increase in dispersity.