Iron Oxide-Based Catalyst for Catalytic Cracking of Heavy Oil

This chapter describes an iron oxide catalyst containing Zr and Al for production of light hydrocarbons by catalytic cracking of petroleum residual oil in a steam atmosphere. The catalyst was hematite structure and useful for decomposition and desulfurization of resid- ual oil. After lattice oxygen of iron oxide reacted with heavy oil fraction of residual oil, oxygen species generated from steam were supplied to iron oxide lattice and reacts with heavy oil fraction, producing light hydrocarbons and carbon dioxide. When the oxygen species were generated from steam, hydrogen species were simultaneously generated from steam. The hydrogen species were transferred to light hydrocarbons, hydrogen sulfide, and residue deposited on the catalyst. Supplies of the hydrogen species to light hydrocar- bons suppressed alkene generation. Generation of hydrogen sulfide indicated decomposi tion of sulfur compounds of residual oil. The sulfur concentration of product oil decreased compared to the concentration of residual oil. Some oxygen species could be transferred to sulfur dioxide. Accordingly, hydrogenation and oxidation by the hydrogen and oxygen species derived from steam provided the decomposition and desulfurization of residual oil with the iron oxide-based catalyst in a steam atmosphere.