Regeneration of aqueous caustic-mercaptide solutions with oxygen and a liquid hydrocarbon

Claim 1

A REFINING PROCESS WHICH COMPRISES (1) CONTACTING IN THE ABSENCE OF FREE-OXYGEN, A SOUR PETROLEUM DISTILLATE WITH AN AQUEOUS SOLUTION COMPRISING CAUSTIC AND A PHENOLIC SOLUBILITY PROMOTER FOR MERCAPTANS, (2) SEPARATING A DISTILLATE REDUCED IN MERCAPTAN CONTENT FROM A SPENT AQUEOUS SOLUTION COMPRISING MERCAPTIDES, CAUSTIC AND PROMOTOR, (3) CONTACTING SAID SPENT SOLUTION, AT A TEMPERATURE BETWEEN ABOUT 80* AND 130* F., IN THE PRESENCE OF A PHENOLIC MERCAPTAN OXIDATION CATALYST, WITH FREE-OXYGEN, IN AN AMOUNT AND FOR A TIME SUFFICIENT TO CONVERT MERCAPTIDES TO DISULFIDES WITHOUT SUBSTANTIAL OXIDATION OF SAID CATALYST, AND IN THE PRESENCE OF A LIQUID PETROLEUM DISTILLATE BOILING BELOW ABOUT 700* F., IN AN AMOUNT BETWEEN ABOUT 10 AND ABOUT 100 VOLUME PERCENT BASED ON AQUEOUS CAUSTIC IN SAID SPENT SOLUTION, (4) SEPARATING DISTILLATE FROM REGENERATED AQUEOUS SOLUTION AND (5) RECYCLING SAID REGENERATED SOLUTION TO STEP (1).