Process for recovery of naphthalene from sulfonic acid solutions

Claim 1

IN REDUCING THE BIOLOGICAL OXYGEN DEMAND OF AND RECOVERING NAPHTHALENE FROM AN AQUEOUS EFFLUENT MIXTURE CONTAINING NAPHTHALENE SULFONATES AND SULFONATES OF POLYMERIZABLE IMPURITIES OF CRUDE NAPHTHALENES INCLUDING SULFONATES OF THIONAPHTHENES, SAID MIXTURE RESULTING FROM TREATING NAPHTHALENE WITH AQUEOUS LIQUORS, THE TREATMENT WHICH COMPRISES: ADDING TO SAID EFFLUENT MIXTURE, AS A POLYMERIZATION CATALYST, AN AMOUNT OF AN ACID SELECTED FROM THE GROUP CONSISTING OF SULFURIC, PHOSPHORIC AND HYDROCHLORIC SUFFICIENT TO PRODUCE AN ACID CONCENTRATION FROM 10% TO ABOUT 50% BUT BELOW THAT AT WHICH SUBSTANTIAL AMOUNTS OF SOLUBLE NAPHTHALENE SALTS ARE FORMED, HEATING THE MIXTURE AT TEMPERATURES OF FROM ABOUT 175* TO ABOUT 350*C., WHEREBY HYDROLYSIS OF THE SULFORNATES AND POLYMERIZATION OF RESULTING POLYMERIZABLE THIONAPHTHENES ARE INITIATED, CONTINUING SAID HEATING UNTIL SAID REACTIONS ARE SUNSTANTIALLY COMPLETE, COOLING THE SOTREATED MIXTURE, WHEREBY THE MIXTURE SEPARATES INTO AN AQUEOUS PHASE AND A NAPHTHALENE-CONTAINING ORGANIC PHASE, DURING SAID TREATMENT, PRODUCING IN SAID MIXTURE A SUFFICIENT CONTENT OF INORGANIC MATERIAL THAT SAID SEPARATED AQUEOUS PHASE HAS A SPECIFIC GRAVITY OF AT LEAST 1.07, AND COLLECTING THE ORGANIC PHASE.