Extraction process for refining lubricating oils

Claim 1

AN IMPROVED PROCESS FOR REFINING A LUBRICATING OIL FRACTION WHICH COMPRISES CONTACTING SAID FRACTION WITH PHENOL IN A PHENOL EXTRACTION ZONE UNDER CONDITIONS FORMING A SOLVENT EXTRACT HASE AND A RAFFINATE PHASE, SEPARATELY REMOVING SAID SOLVENT EXTRACT PHASE AND SAID REFFINATE PHASE FROM SAID EXTRACTION ZONE, HEATING SAID EXTRACT PHASE TO A TEMPERATURE OF FROM 450*C TO 750*F., VAPORIZING THE MAJOR PORTION OF THE PHENOL FROM SAID EXTRACT PHASE IN A FIRST VAPORIZING ZONE MAINTAINED AT A TEMPERATUE WITHIN SAID LAST-NAMED TEMPERATURE RANGE, CONDUCTING THE HEATED EXTRACT TO A FIRST STRIPPING ZONE, STRIPPING RESIDUAL PHENOL FROM SAID EXTRACT WITH A NONAQUEOUS STRIPPING GAS IN SAID STRIPPING ZONE, REMOVING STRIPPED EXTRACT FROM SAID STRIPPING ZONE, HEATING SAID RAFFINATE PHASE TO A TEMPERATURE OF FROM 450* TO 750*F., VAPORIZING THE MAJOR PORTION OF THE PHENOL PRESENT IN SAID RAFFINATE PHASE THEREFROM IN A SECOND VAPORIZING ZONE MAINTAINED AT A TEMPERATURE WITHIN SAID TEMPERATURE RANGE, CONDUCTING THE HEATED RAFFINATE TO A SECOND STRIPPING ZONE, REMOVING RESIDUAL PHENOL FROM SAID RAFFINATE WITH A NON-AQUEOUS STRIPPING GAS IN SAID SECOND STRIPPING ZONE, CONDUCTING STRIPPED HOT RAFFINATE FROM SAID SECOND STRIPPING ZONE INTO A HYDROFINING ZONE, CONTACTING SAID RAFFINATE WITH HYDROGEN IN SAID HYDROFINING ZONE AND RECOVERING THEREFROM A REFINED LUBRICATING OIL.