The Influence of Temperature and Catalyst Additives on Catalytic Cracking of a Heavy Fuel Oil

The effects of reaction temperature and catalyst additives on the fluid catalytic cracking (FCC) products yield have been studied through cracking of a heavy fuel oil obtained from Tehran refinery. The catalytic performance was assessed using a commercial equilibrium USY FCC catalyst (E-Cat) in a fixed-bed micro-activity test unit. Two types of ZSM-5 zeolites with different SiO2/Al2O3 ratios together with MCM-41 were tested as additives. Different reaction temperatures of 550, 600 and 640 degrees C were investigated for the corresponded E-Cat/Additives. MAT results showed that more propylene and the highest propylene to ethylene ratio can be obtained via E-Cat/MCM-41 at 550 degrees C. Applying ZSM-5 zeolite led to enhancement in total olefins production. Different behaviors were observed using two ZSM-5 additives. Butenes production followed a similar fashion through all additives at the three temperatures tested.