Abstract:
THE METHOD COMPRISES ADDING AN INHIBITOR TO A HYDROFINISHED DISTILLATE OR A HYDROFINISHED RAFFINATE FROM A DISTILLATE PRIOR TO THE TIME THAT SAID DISTILLATE OR SAID RAFFINATE IS CONTACTED WITH AIR. THE INHIBITOR IS A MEMBER SELECTED FROM THE GROUP CONSISTING OF HINDERED PHENOLS, AMINES, AND METAL COMPLEXES OF MANNICH CONDENSATION PRODUCTS FROM PHENOLS, ALDEHYDES, AND POLYAMINES. IF THE DISTILLATE HAS BEEN HYDROFINISHED IN A TWO-STAGE PROCESS UNDER RELATIVELY SEVERE CONDITIONS, AN INHIBITOR MAY BE ADDED TO THE EFFLUENT FROM THE FIRST STAGE AND AN INHIBITOR MAY BE ADDED TO THE PRODUCT FROM THE SECOND STAGE.
Abstract:
1. A PROCESS FOR THE PRODUCTION OF A COLORLESS MINERAL OIL, WHICH PROCESS COMPRISES CONTACTING A DEWAXED MINERAL LUBRICATING OIL DISTILLATE OR A DEWAXED AND SOLVENTEXTRACTED MINERAL LUBRICATING OIL DISTILLATE OF REDUCED AROMATIC HYDROCARBON CONTENT IN A FIRST REACTION ZONE WITH A SULFACTIVE HYDROGENATION CATALYST IN THE PRESENCE OF HYDROGEN AND UNDER HYDROGENATION AN DESULFURIZATION CONDITIONS TO PRODUCE A HYDROGENATED AND DESULFURIZED PRODUCT; CONTACTING SAID HYDROGENATED AND DESULFURIZED PRODUCT IN A SECOND REACTION ZONE WITH A SECOND CATALYST COMPRISING A GROUP VIII NOBLE METAL EPOSITED UPON A LARGE-PORE-DIAMETER ALUMINA HAVING A SURFACE AREA OF ABOUT 150 SQUARE METERS PER GRAM TO ABOUT 500 SQUARE METERS PER GRAM AND AN AVERAGE PORE DIAMTER OF ABOUT 100 A. TO BOUT 200 A. IN THE PRESENCE OF HYROGEN AND AT A TEMPERATURE OF AT LEAST 450*F. A LHSV OF ABOUT 0.25 TO ABOUT 1 VOLUME OF HYDROCARBON PER HOUR PER VOLUME OF CATALYST, A HYDROGEN ADDITION RATE OF ABOUT 1,500 SCFB TO ABIUT 7,00 SCFB, AND A HYDROGEN PARTIAL PRESSURE OF AT LEAST 500 P.S.I.G. SAID TEMPERATURE IN SAID SECOND REACTION ZONE HAVING A MAXIMUM VALUE OF 500*F. AND RECOVERING SAID COLORLESS MINERAL OIL FROM THE EFFLUENT FROM SAID SECOND REACTION ZONE.