Double solvent refining of tar

Claim 1

A PROCESS FOR THE FRACTIONATION OF PRIMARY LOW-TEMPERATURE TAR BY DOUBLE SOLVENT EXTRACTION OF SAID TAR OBTAINED FROM THE LOW-TEMPREATURE CARBONIZATION OF BITUMINOUS COAL, WHICH COMPRISES THE STEPS OF FEEDING TO A LIQUID-LIQUID EXTRACTION ZONE ONE VOLUME OF SAID PRIMARY LOW-TEMPERATURE TAR, FROM 0.5 TO 5 VOLUMES OF A FIRST SOLVENT CONSISTING OF AN AQUEOUS METHANOL SOLUTION CONTAINING ABOUT 40 TO 80 WEIGHT PRECENT METHANOL AND THE BALANCE WATER, AND FROM 0.5 TO 5 VOLUMES OF A SECOND SOLVENT CONSISTING OF A PARAFFINIC NAPHTHA FRACTION BOILING WITHIN THE RANGE OF 60 TO 130*C. AND HAVING A DENSITY OF LESS THAN 0.8, THE VOLUME RATIO OF THE FIRST AND SECOND SOLVENTS BEING MAINTAINED BETWEEN 0.5 AND 2, MAINTAINING SAID TAR, AQUEOUS METHANOL AND NAPHTHA FRACTION UNDER LIQUID-LIQUID CONTACTING CONDITIONS AT A TEMPERATURE BETWEEN 50 AND 150*C. WHEREBY THREE PHASES ARE FORMED, RECOVERING AN AQUEOUS METHANOL EXTRACT CONATINING TAR ACIDS AS A FIRST PHASE, RECOVERING A NAPTHA EXTRACT AS A SECOND PHASE, AND RECOVERING AN INSOLUBLE PITCH RESIDUE AS A THIRD PHASE.