ABSTRACT
Hydrotreatment is the conventional means for removing of sulfur from petroleum fractions. Removal of sulfur is required to eliminate a major poison in subsequent processing (e.g., by naphtha reforming) or to meet environmental legislation (e.g., in middle distillates). Commercially used catalysts for reformer feedstock hydrotreatment belong to the broad class of molybdenum sulfide catalysts, which are applied for the hydroprocessing of a variety of feedstocks, including middle distillates and gas oils. The major requirements to be met by naphtha hydrotreatment catalysts are high activity and selectivity for hydrogenolysis of C-S bonds, with low selectivity for cracking of C-C bonds. In addition, they should exhibit reduced activity for hydrogenation of aromatic compounds in order to maintain octane number and reduce the hydrogen consumption. The catalyst should also possess long-term stability and low sensitivity to poisons.
