Recovering solvent from process steam

Claim 1

IN THE EXTRACTION OF LUBRICATING OIL STOCKS BY MEANS OF TWO IMMISCIBLE SOLVENTS, A FIRST SOLVENT FOR THE PARAFFINIC CONSTITUENTS AND A SECOND SOLVENT FOR THE NAPHTHENIC CONSTITUENTS WHEREIN SAID FIRST SOLVENT IS REMOVED FROM THE RAFFINATE AND EXTRACT FRACTIONS BY DISTILLATION AND SAID SECOND SOLVENT IS THEN REMOVED FROM THE RAFFINATE AND EXTRACT FRACTIONS BY STRIPPING THEM WITH STEAM, WHEREIN THE STREAM OF STEAM AND SAID SECOND SOLVENT FROM THE STRIPPING OPERATION ARE FRACTIONATED TO FORM A FIRST OVERHEAD AZEOTROPIC FRACTION COMPRISING STEAM AND SAID SECOND SOLVENT, THE IMPROVEMENT WHICH COMPRISES IN COMBINATION CONDENSING SAID FIRST OVERHEAD AZEOTROPIC FRACTION, CONTACTING THE RESULTING CONDENSATE WITH SAID FIRST SOLVENT WHEREBY A PORTION OF SAID SECOND SOLVENT IS EXTRACTED FROM SAID CONDENSED FIRST AZEOTROPIC FRACTION, FRACTIONATING THE RESULTING RAFFINATE TO FORM A SECOND OVERHEAT AZEOTROPIC FRACTION COMPRISING STEAM AND SAID SECOND SOLVENT AND A BOTTOMS FRACTION COMPRISING SUBSTANTIALLY PURE WATER AND RECYCLING SAID SECOND OVERHEAD AZEOTROPIC FRACTION BY BLENDING IT WITH SAID FIRST OVERHEAD AZEOTROPIC FRACTION.