Increasing the base number of calcium petroleum sulfonate

Claim 1

A PROCESS FOR JPRODUCING A LUBRICANT ADDITIVE WHICH COMPRISES THE STEPS OF: CONTACTING A LUBRICANT ADDITIVE COMPOSITION COMPRISING A COMPOUND SELECTED FROM THE GROUP CONSISTING OF A PETROLEUM SULFONIC ACID AND A CALCIUM PETROLEUM SULFONATE, WHEREIN THE SULFONATED STOCK IS HIGHLY PARAFFINIC, DEASPHALTED AND SOLVENT REFINED PETROLEUM FRACTION HAVING A VISCOSITY OF ABOUT 180 TO 230 SUS AT 210*F. AND HAVING A VISCOSITY INDEX OF AT LEAST ABOUT 85, WITH METHANOL, IN AN AMOUNT EQUAL TO 5 TO 100 VOLUME PERCENT JOF SAID COMPOSITION, AN AMOUNT OF A CALCIUM COMPOUND SELECTED FROM THE GROUP CONSISTING OF CALCIUM OXIDE, AND CALCIUM HYDROXIDE TO PROVIDE 2 TO 6 TIMES THE AMOUNT CHEMICALLY EQUIVALENT TO A DESIRED OVERBASING, AND A SUFFICIENT AMOUNT OF AN AMMONIUM COMPOUND SELECTED FROM THE GROUP CONSISTING OF AMMONIUM CARBONATE, AMMONIUM BICARBONATE AND AMMONIUM CARBAMATE TO FURNISH CARBON DIOXIDE BY DECOMPOSITION TO REACT WITH ALL OF SAID CALCIUM COMPOUND, WHILE MAINTAINING THE UNCOMBINED WATER CONTENT OF THE RESULTING MIXTURE BELOW ABOUT 7 VOLUME JPERCENT OF THE AMOUNT OF SAID METHANOL; AND HEATING TO A TEMPERATURE IN THE RANGE OF 150 TO 500*F. UNTIL BASIC VAPORS NO LONGER ARE EVOLVED