Diaryl sulfones and their manufacture

Claim 1

A PROCESS OF PREPARING A NORMALLY LIQUID MIXTURE OF DIXYLYL SULFONE ISOMERS COMPRISING HEATING A MIXTURE OF C8 AROMATIC HYDROCARBONS CONTAINING 35 TO 50% METAXYLENE, 10 TO 26% PARAXYLENE, 5 TO 25% ORTHOXYLENE AND ABOUT 5 TO 15% ETHYLBENZENE IN THE PRESENCE OF SULFURIC ACID TO EFFECT REACTION THEREBETWEEN AND CONVERT C8 AROMATIC HYDROCARBONS TO THE CORRESPONDING ARYL SULFONIC ACIDS, HEATING THE SO-PRODUCED REACTION MIXTURE AT A TEMPERATURE BETWEEN 145* AND 165* C., REFLUXING C8 AROMATIC HYDROCARBONS FROM THE REACTION ZONE DURING THE REACTION PERIOD, SEPARATING WATER FROM THE REFLUXING CONDENSATE BEFORE ITS RETURN TO THE REACTION ZONE, CONTINUING REACTION BETWEEN SO-FORMED ARYL SULFONIC ACIDS AND SULFURIC ACID UNTIL MORE THAN 20% BUT LESS THAN 45% OF THE SO-FORMED ARYL SULFONIC ACIDS ARE CONVERTED TO A NORMALLY LIQUID MIXTURE OF DIXYLYL SULFONES, AS PRODUCED BY THE SAID REACTIONS BETWEEN SAID MIXTURE OF C8 AROMATIC HYDROCARBONS AND SULFURIC ACID, AND RECOVERING THE SAID NORMALLY LIQUID MIXTURE OF DIXYLYL SULFONES FROM THE REACTION MASS.