Effect of reaction temperature on cracking of residual oil over nickel oxide ore.

Abstract

Kuwait vacuum residue was cracked over a nickel oxide ore catalyst and over porcelain Raschig rings at 450-650°C, and the yields and properties of the cracked products were investigated. The gas yield increased and the yield of Fraction R (boiling point 510°C+) decreased with increase in the reaction temperature, while coke yield remained almost constant. Higher yields of hydrogen and distillates were observed over the catalyst than over Raschig rings. It was inferred that the cracking and coking activities of the catalyst were due to the partially reduced state of the iron and nickel oxides which were reduced by hydrocarbon vapors during the cracking reaction. The cracked oil obtained over the nickel oxide ore catalyst had high contents of C10-C15 linear α-olefins.