CATALYTIC GASOLINE DESULFURIZATION METHOD HAVING ALSO OLEFIN SELECTIVE REMOVAL FUNCTION

摘要

A catalytic gasoline desulfurization method having also an olefin selective removal function, comprising: when a catalytic gasoline is pre-hydrotreated, cutting into a light fraction, an intermediate fraction, and a heavy fraction; performing a liquid-liquid extraction desulfurization treatment with respect to the intermediate fraction to produce a sulfur-depleted oil and a rich solvent containing a sulfur-rich oil; light fraction back-extracting the rich solvent, using C₅ olefin therein to replace a macromolecular acyclic olefin in the sulfur-rich oil, thus gathering together C₅ isomeric alkene, a cyclic olefin, and a sulfide in the sulfur-rich oil; performing hydrogenation, olefin reduction, and desulfurization treatments on the heavy fraction together with the sulfur-rich oil removed from the back-extracted solvent, saturating the olefin in the oil, and finally preparing together with the sulfur-depleted oil to produce an all-fraction gasoline. The sulfur content of the catalytic gasoline produced per the method can be reduced to 10 ppm or less, thus ensuring reduced octane loss while reducing the olefin content of the catalytic gasoline.