OLEFIN ADDITION FOR SELECTIVE NAPHTHA DESULFURIZATION WITH REDUCED OCTANE LOSS

摘要

Naphtha is desulfurized with reduced or no octane loss by adding four to six carbon atom olefins to a raw naphtha feed to form an olefin-enriched feed, which is catalytically converted to an iso-olefinic naphtha and then selectively hydrodesulfurized. The raw feed is typically a cracked naphtha, with the added olefins comprising isobutene. The conversion also forms higher boiling sulfur compounds from thiophenes and preferably only a heavy iso-olefinic naphtha fraction containing the iso-olefins and higher boiling sulfur is desulfurized.