Method of refining oil with a selective solvent

Claim 1

A PROCESS FOR THE LIQUID-LIQUID SOLVENT EXTRACTION OF A CHARGE OIL CONTAINING AROMATIC AND NON-AROMATIC HYDROCARBONS WHICH COMPRISES CONTACTING SAID CHARGE OIL IN AN EXTRACTION ZONE WITH LIQUID FURFURAL TO FORM A LIQUID RAFFINATE PHASE AND A LIQUID EXTRACT PHASE, INTRODUCING SAID RAFFINATE PHASE INTO A FIRST FRACTIONATION ZONE, RECOVERIG OVERHEAD FROM SAID FIRST ZONE AN AZEOTROPIC MIXTURE CONTAINING FURFURAL, WATER AND A HYDROCARBON, WITHDRAWING FROM SAID FIRST ZONE A RAFFINATE SUBSTANTIALLY FREE FROM FURFURAL, INTRODUCING SAID LIQUID EXTRACT PHASE INTO A SECOND ZONE FRACTIONATION ZONE, RECOVERING OVERHEAD FROM SAID SECOND ZONE AN AZEOTROPIC MIXTURE CONTAINING FURFURAL, WATER AND A HYDROCARBON, WITHDRAWING FROM SAID SECOND ZONE AN EXTRACT SUBSTNTIALLY FREE OF FURFURAL, CONDENSING THE OVERHEAD AZEOTROPIC MIXTURES FROM SAID FIRST AND SECOND ZONES AND SEPARATING THEREFROM IN A SETTLING ZONE THREE LIQUID PHAES: AN UPPER OIL-RICH PHASE, INTERMEDIATE WATER-RICH PHASE AND A BOTTOM FUFFURAL-RICH PHASE CONTAINING DISSOLVED WATER, SAID SETTLING ZONE BEING MAINTAINED AT A TEMPERATURE IN THE RANGE 75-125* F., AND RECYCLING A PORTION OF SAID FURFURAL-RICH PHASE TO SAID EXTRACTION ZONE AND TO SAID FIRST AND SECOND FRACTIONATION ZONES, THE AMOUNT OF WATER DISSOLVED IN SAID RECYCLED FURFURAL-RICH PHASE BEING SUFFICIENT TO FORM THE AFORESAID AZEOTROPIC MIXTURES PRODUCED OVERHEAD FROM SAID FIRST AND SECOND FRACTIONATION ZONES, THE WATER CONTAINED IN SAID FURFURAL-RICH PHASE RECYCLED TO SAID EXTRACTION ZONE AND TO SAID FIRST AND SECOND FRACTIONATION ZONES BEING THE ONLY WATER INTRODUCED SAID ZONES.