Patent ID: 7875185

Claim:
A process for removing residual sulfur compounds from a caustic feed stream, comprising, in combination, a) obtaining a caustic feed stream from a lower layer of a gravity separator, wherein caustic entering the gravity separator has been previously oxidized in an oxidization process, and wherein residual sulfur compounds in the caustic feed stream comprise less than 500 weight ppm measured as elemental sulfur; b) introducing the caustic feed stream of step a) into a polishing unit; c) introducing an oxidant into the polishing unit; d) admixing and contacting the caustic feed stream and oxidant within the polishing unit in the presence of a catalyst bed comprising a metal phthalocyanine catalyst supported on a catalyst support; e) converting mercaptans that are present as part of the sulfur compounds in the caustic feed stream to disulfides; f) adsorbing on the catalyst support the disulfides formed in step e) and disulfides introduced into the polishing unit as part of the sulfur compounds in the caustic feed stream; and g) removing from the polishing unit a polished caustic stream product comprising less than 20 weight ppm of sulfur compounds measured as elemental sulfur.