Aqueous-phase catalytic hydrogenation and hydrogenolysis reactions of sulfur- and nitrogen-containing compounds in oil fractions

Abstract

This article reviewed the research related to the hydrogenation and hydrogenolysis of nitrogen-containing and sulfur-containing heterocyclic aromatic organic compounds found in most oil fractions that are used to formulate fuels (gasoline and diesels). Thiophenes, benzothiophenes and quinoline were studied as main components of heteroatom like S and N in fuels. Studies involved the use of organometallic species or compounds of ruthenium, rhodium and tungsten that are able to convert N and S aromatics in a two-phase immiscible medium, as it is the case for water or methanol and naphtha coming from Fluid Catalytic Cracking processes (FCC). Ruthenium species and compounds promoted hydrogenation of heteroaromatic rings in naphtha while rhodium complexes promoted hydrogenolysis. A tungsten hydrosoluble complex showed both hydrogenation and hydrogenolysis in an aqueous/organic medium, depending upon reaction conditions.