Review of Current Advances in Hydrotreating Catalyst Support

The reduction in conventional oil resources, coupled with the predicted increase in oil demand in the coming years, has necessitated the exploration of unconventional reserves like oil sands. However, crude oil from these unconventional sources consists of large amounts of impurities like sulfur and nitrogen, which need to be removed via upgrading processes like hydrotreating. Alumina-supported catalysts are currently the predominantly used catalysts for hydrotreating but the strong metal-support interactions present in these catalysts inhibit their activity, thereby limiting their efficiency. This paper reviews recent progress made to develop novel catalysts with different supports, which can have better hydrotreating conversions than alumina-supported catalysts. From the several literatures reviewed, it was noted that, finding the best catalysts with improved efficiency came with challenges related to getting the optimal metal-support combinations and interactions, support-addition techniques and metal-loading methods, all of which have significant impacts on the catalyst's activity. Some supports such as mesoporous titania-alumina, zirconia-alumina, multi-walled carbon nanotubes and ethylenediamine-functionalized graphene were demonstrated to have promising potential when used as carriers for NiMo and CoMo metals. It was suggested that the feasibility of these catalysts for use in commercial operations to obtain maximum conversions should be considered.