Relationship between initial catalyst activity and the surface area of silica supports for the upgrading of an Australian coal-derived liquid

Abstract Four silica-based nickel-molybdenum catalysts of differing surface areas and constant metal loading have been tested in a batch autoclave reactor for their ability to hydrogenate and remove phenolic oxygen from a coal-derived liquid. It was found that initial catalytic activity increased as the surface area of the support increased, reaching a maximum, after which the activity was observed to fall. Variation in active site dispersions are considered to be the major factor for the observed changes in activity. When compared to similar alumina-supported catalysts of various surface areas (including a Shell 424 reference), the silica-based catalysts were found to possess lower activities for heavy oil upgrading.