Production of dinonylnaphthalene sulfonates

Claim 1

A PROCESS FOR THE PRODUCTION OF OIL-SOLUBLE DINOYLNAPTHALENE SULFONATE, SAID PROCESS COMPRISING THE STEPS OF: (A) SULFONATING DINONYLNAPHTHALENE DISSOLVED IN 1-4 PARTS OF NONAROMATIC HYDROCARBON SOLVENT, HAVING A BOILING POINT OF LESS THAN 150*C., PER PART OF DINONYLNAPTHALENE WITH A SULFONATING AGENT SELECTED FROM THE GROUP CONSISTING OF OLEUM AND SULFUR TRIOXIDE; (B) QUENCHING THE SULFONIC ACID REACTION MIXTURE WITH AN AMOUNT OF WATER IN THE RANGE OF ABOUT 1.10 TO ABOUT 0.20 PART BY WEIGHT PER PART OF TOTAL SO3 IN SAID SULFONATING AGENT; (C) DILUTING THE WATER-QUENCHED REACTION MIXTURE WITH NONAROMATIC HYDROCARBON SOLVENT TO A TOTAL SOLVENT TO DINONYLNAPHTHALENE RATIO OF 2.5 TO 4.5 PARTS OF SOLVENT PER PART OF DINONYLNAPTHALENE (WEIGHT BASIS); (D) ALLOWING THE REACTION MIXTURE TO STRATIFY AND REMOVING THE SLUDGE; (E) NEUTRALIZING THE SULFONIC ACID WITH A BASIC COMPOUND SELECTED FROM THE GROUP CONSISTING OF ALKALI METAL HYDROXIDES, ALKALI METAL CARBONATES, AMMONIUN HYDROXIDE, AND AMMONIUM CARBONATE; (F) WASHING THE SOLUTION OF SULFONATE WITH FROM ABOUT 2.5 TO ABOUT 4 PARTS OF WATER PER PART OF DINONYLNAPHTHALENE; (G) ALLOWING THE AQUEOUS AND HYDROCARBON LAYERS TO STRATIFY AND REMOVING THE AQUEOUS LAYER; (H) REMOVING SOLVENTS AND RESIDUAL WATER FROM THE DINONLYNAPHTHALENE SULFONATE.