Process for deep desulfurization of cracked gasoline with minimum octane loss

Abstract

The present invention provides a process for deep desulphurization of cracked gasoline with minimum octane loss of about 1-2 units. In this process full range cracked gasoline from FCC, Coker, Visbreaker etc is sent to Diolefin Saturation Reactor for selective saturation of diolefins. After saturation of diolefins, the stream is sent to Splitter for splitting into three cuts i.e Light Cut (IBP-70° C.), Intermediate Cut (70-90° C.) and Heavy Cut (90-210° C.). The Light Cut which contains majority of the high octane olefins and mercaptan sulfur is desulfurized with caustic treatment using Continuous Film Contactor (CFC). The sulfur in the Intermediate Cut is also predominantly mercaptans and the cut can be desulfurized by caustic treatment using CFC along with Light cut or separately desulfurized before being sent for isomerization. The Heavy Cut containing mainly thiophinic sulfur compounds is treated either by using conventional HDS process or reactive adsorption process.