Mercaptan conversion process

Claim 1

In a process for the reduction of mercaptan compounds in a petroleum distillate which comprises contacting said petroleum distillate with a caustic possessing a pH of from about 8 to a pH of about 10 to extract naphthenic acids at a temperature of about 10° C. to about 100° C. and a pressure of from about 1 atmosphere to about 100 atmospheres and catalytically treating said petroleum distillate with an oxygen-containing gas atmosphere in the presence of a catalyst consisting essentially of a metal phthalocyanine compound dispersed on a solid catalytic support in a caustic medium possessing a pH of from about 9 to a pH of about 14 at a temperature of from about 10° C. to about 100° C., a pressure of from about 1 atmosphere to about 100 atmospheres and a liquid hourly space velocity of from about 0.5 to about 10 to substantially reduce mercaptan content of said petroleum distillate the improvement which consists of passing said petroleum distillate subsequent to contacting with said caustic and before catalytic treatment thereof through an unimpregnated charcoal bed selected from the group consisting of a charcoal derived from lignite coal, bituminous coal, vegetable sources, peat, petroleum black extrusions and bone char to remove catalyst-toxin precursors from said distillate at a temperature of from about 10° C. to about 100° C., a pressure of from about 1 atmosphere to about 10 atmospheres and a liquid hourly space velocity of from about 0.5 to about 10.