Patent ID: 7736491

Claim:
A process for the fluid catalytic cracking of mixed feedstocks of hydrocarbons from different sources, in a riser reactor and in the presence of a zeolitic catalyst, under cracking conditions for producing light products such as LPG, said mixed feedstocks comprising feeds A and B, with feed B being more refractory to cracking, wherein said process comprises simultaneous segregated injections of feeds A and B, in distinct riser locations, and includes the steps of: a) injecting feed A at a location at the bottom of the riser reactor, which sets the base of the riser reactive section, with a temperature rise ranging from 10 to 50° C.; and b) injecting feed B, at an amount of from 5 to 50 wt % based on the total mixed feedstock, downstream, after maximum LPG production from feed A, at one or more riser locations between 10% and 80% of the riser reactive section; wherein the injection conditions in a high dispersion degree of feed B comprise: dispersion steam ranging from 5 to 20%; and a temperature equal to or higher than the injection temperature of feed A; wherein the catalyst to oil ratio is maintained during the cracking of feeds A and B, and the light products resulting from the cracking process are recovered in a higher amount than would be obtained if feed B was injected in the base of the riser reactive section.