Oxygen chemisorption and activity studies on alumina- and carbon-supported hydrodesulphurization catalysts

Abstract

Co---Mo and a series of Mo catalysts were prepared on alumina and carbon supports and were characterized by low temperature oxygen chemisorption (LTOC) at −78°C. The reactivity of sulphided catalysts for thiophene hydrodesulphurization (HDS) and cyclohexene hydrogenation (HYD) were measured in a flow microreactor at atmospheric pressure. Three commercial HDS catalysts were also subjected to these studies for comparison. A good correlation was found between HDS activity and oxygen uptake. Carbon-supported catalysts had a much higher HDS activity and lower HYD activity than alumina-supported catalysts. The improved HDS activity was related to the better dispersion of the molybdenum sulphide phase on the carbon support