Fluid catalytic cracking (FCC)

Crude oil comprises hundreds of molecules that boil over a wide temperature range. The lighter products can be separated directly by distillation into LPG, gasoline, naphtha, kerosene, and diesel fuels. Heavier products (BP > 650°F/344°C) include vacuum gas oils and resids. Thermal and catalytic cracking processes in petroleum refining reduce the molecular weight of these heavier constituents and produce more valuable lighter products such as LPG, gasoline and diesel fuels.

Catalytic cracking was first commercialized in 1936 by Eugene Houdry. This fixed bed process was a major improvement over the thermal cracking processes it replaced due to the improved yield distribution and superior product properties. Multiple vessels were utilized that alternated between cracking, stripping, regeneration, and purge cycles. This configurationwas quickly replaced by amoving bed reactor and a separate regenerator or kiln that first used a bucket lift to move the pelleted catalyst followed later by a pneumatic air lift system. The last of these units was built around 1960.

Standard Oil of New Jersey developed their own cracking process rather than pay the large royalty being asked at the time. They commercialized the fluid catalytic cracking (FCC) process in three years, starting in 1939 and culminating in 1942 with the startup of PCLA#1 at their Baton Rouge, Louisiana refinery. The inherent superiority of the fluid process to transfer both heat and catalyst ultimately made it the catalytic cracking process of choice.