Emulsion dewaxing of mineral oils accompanied by intensive agitation

Claim 1

IN A METHOD OF DEWAXING A WAXY MINERAL OIL, THE COMBINATION OF STEPS COMPRISING: (1) MIXING THE WAXY MINERAL OIL WITH ASUBSTANTIAL PROPORTION OF A DEWAXING SOLVENT FOR THE MINERAL OIL BUT WHICH IS SUBSTANTIALLY A NON-SOLVENT FOR SOLID WAX; (2) COOLING THE MIXTURE TO A DEWAXING TEMPERATURE AT WHICH THE WAX SOLIDIFIES, THEREBY FORMING A DISPERSION OF SOLID WAX PARTICLES IN A LIQUID OIL PHASE WHICH IS A SOLUTION OF THE OIL AND THE SOLVENT; (3) SUBJECTING THE COOLED MIXTURE TO VIBRATIONS HAVING A FREQUENCY OF 5,000-50,000 CYCLES PER SECOND; (4) INTIMATELY MIXING THE RESULTING DISPERSION OF SOLID WAX DISPERSED IN THE OIL PHASE WITH A SUBSTANTIAL PROPORTION, AT LEAST EQUAL IN VOLUME TO THE VOLUME OF THE OIL PHASE, OF A SUBSTANTIALLY POLAR AUXILIARY LIQUID WHICH IS SUBSTANTIALLY IMMISCIBLE THEREWITH AND WHICH HAS A DIELECTRIC CONSTANT HIGHER THAN THAT OF THE OIL PHASE, AND WITH A MINOR AMOUNT OF A SURFACE-ACTIVE AGENT, THE ENTIRE SYSTEM BEING ESSENTAILLY AT THE DEWAXING TEMPERATURE, WHEREBY TWO LIQUID PHASES RESULT, AN OIL PHASE CONSISTING ESSENTIALLY OF MINERAL OIL AND SOLVENT AND AN AUXIALLARY LIQUID PHASE CONTAINING DISSOLVED SAID SURFACE-ACTIVE AGENT, AND CORRELATING THE DIAELECTRIC CONSTANTS OF THE TWO LIQUID PHASES SO THAT THE CONTACT ANGLE IN THE OIL PHASE IS AT LEAST 90*, WHEREBY THE SOLIDS WAX IS PREFERENTIALLY WETTED BY THE AUXILIARY LIQUID PHASE AND IS TRANSFERRED THERETO TO PRODUCE A DISPERSION OF THE SOLID WAX IN THE AUXILIARY LIQUID PHASE AS THE CONTINUOUS PHASE, WHILE THE OIL PHASE IS SUBSTANTIALLY FREE FROM WAX; (5) STRATIFYING AND SEPARATING THE OIL PHASE FROM THE AUXILIARY LIQUID PHASE CONTAINING THE DISPERSION OF SOLID WAX; THE AGITATION IN STEP (3) BEING SUFFICIENT TO SUBSTANTIALLY INCREASE THE RATE OF TRANSFER OF SOLID WAX FROM THE OIL PHASE INTO THE AUXIALLARY LIQUID PHASE AND TO SUBSTANTIALLY REDUCE THE PROPORTION OF CONTAMINATING OIL IN THE SEPARATED AUXIALLARY LIQUID-WAX PHASE.