Seventy-five (75) kilograms of isopropyl alcohol and 25 kilograms of deionized water were charged in a 50 gallon glass lined reactor. The reactor agitator (three armed retrieve curve impeller) was started at 100 RPM and full cooling (water at 8° to 10° C.) was applied to the reactor jacket. Eighteen (18) kilograms of 93 percent sulfuric acid (technical grade) were added slowly to the reactor, after which 30 kilograms of technical grade distearyl dimethyl ammonium methylsulfate (obtained from Zeeland Chemical Co., d Cambrex Company formerly Hexcel Company of Zeeland, Mich.) were charged in the reactor. The reactor loading port was closed and cooling water was applied to the reactor reflux condenser and the agitator speed adjusted to 150 RPM. The reactor was heated to approximately 840° C. using hot water supplied to the reactor jacket. The reaction was effected for 4 hours under a slight reflux after which cooling was applied to initiate the crystallization. The mixture was agitated for two hours under full cooling at 16° to 18° C. before transferring to a 70 gallon agitated Nutsche vacuum filter. The filtrate was drained and collected in a storage vessel for solvent recovery or disposal. The wet cake was reslurried with 100 kilograms of the second wash filtrate from the previous batch (containing an approximate 75:25 ratio of isopropanol and water) for 30 minutes, after which the filtrate (about 100 kilograms) was drained by vacuum filtration and collected in order to be used as the solvent system for the next synthesis batch. After additional reslurry washes were performed using wash filtrates from a previous batch, the wet cake was discharged from the filter and recrystallized from 100 kilograms of isopropanol In a 50 gallon glass lined reactor. This was performed by dissolving the materials under agitation at 600° C., cooling and recovering the wet dimethyl distearyl ammonium bisulfate cake by filtration. After vacuum drying, 22.27 kilograms (75.8 percent yield) of recrystallized distearyl dimethyl ammonium bisulfate were recovered. Analyticals: melting point (DSC) 91.4° C., H2O content 0.65 percent, bisulfate content (by titration) 14.65 percent.
