This test method provides a means of determining sulfonate content and of classifying and characterizing natural and synthetic petroleum sulfonate products by sulfonate content and average molecular weight. Purity of sodium sulfonate products is measured by basicity and inorganic salt contents and the reserve alkalinity of alkaline earth sulfonates by the total base number.

1.1 This test method covers the analysis of refined and crude natural and synthetic oil-soluble sulfonate products. Resins, if present, are recovered with the oil phase and carboxylates are recovered as sulfonates.

1.2 This test method covers the determination of mineral oil, sodium sulfonate, inorganic salts, water, basicity or acidity, average molecular weight, and relative density of sodium sulfonate products.

1.3 This test method covers the determination of mineral oil, sulfonate, water, base number, average molecular weight, and relative density of calcium, barium, magnesium, and ammonium sulfonate products.

1.4 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.

1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.