Sulfate can be rapidly and easily titrated thermometrically using a standard solution of Ba2+ as titrant. In industry, this procedure is applied to the determination of sulfate in wet-process phosphoric acid (see Application Bulletin AB-308). This Application Bulletin deals with the determination of sulfate in granular fertilizers such as MAP (monoammonium phosphate), DAP (diammonium phosphate), and TSP (triple superphosphate). Results are reported as percentage of elemental sulfur, %S.
