Process of dewaxing petroleum oils and the like

Claim 1

IN THE DEWAXING OF MINERAL OILS, SHALE OILS, TAR OILS, AND THEIR FRACTIONS AND RESIDUES, BY CENTRIFUGING THE OIL IN THE PRESENCE OF AN ADDED OILDISSOLVING AND WAX-PRECIPITATING SOLVENT, SAID SOLVENT FORMING WITH THE OIL AN OIL SOLUTION CONTAINING PRECIPITATED WAX CRYSTALS, THE PROCESS WHICH COMPRISES FORMING IN THE CENTRIFUGING LOCUS, AND ADJACENT THE OIL SOLUTION, A LAYER OF AN AUXILIARY LIQUID HAVING A SPECIFIC GRAVITY INTERMEDIATE THE SPECIFIC GRAVITIES OF THE OIL SOLUTION AND THE WAX, SAID AUXILIARY LIQUID BEING SUBSTANTIALLY INSOLUBLE IN THE OIL SOLUTION AND HAVING A SURFACE TENSION, RELATIVE TO THE OIL SOLUTION, WHICH IS SUFFICIENTLY LOW TO ALLOW THE WAX TO PASS INTO SAID LAYER IN THE FORM OF SEPARATE CRYSTALS WHILE PREVENTING PENETRATION OF OIL INTO SAID LAYER, AND DURING THE CENTRIFUGING OPERATION, PASSING WAX CRYSTALS SEPARATELY THROUGH THE BOUNDARY SURFACE BETWEEN SAID OIL SOLUTION AND LAYER WHILE DISPLACING OIL FROM THE WAX AT SAID LAYER, THEREBY DEOILING THE WAX IN SAID LOCUS.