BS 6829 discusses the analysis of surface-active agents. BS 6829-3.1 belongs to the BS 6829 multi-series and discusses the method for the determination of the mean relative molecular mass of technical straight-chain sodium alkylbenzenesulfonates.
BS 6829-3.1 is only applicable to straight-chain alkylbenzenes since branched-chain types will give chromatograms from which it is impossible to identify and calculate the relative molecular mass for individual chains.
BS 6829-3.1 on method for the determination of mean relative molecular mass of technical straight-chain sodium alkylbenzenesulfonates is useful for:
When using the two-phase titration for the determination of anionic active matter content, it is
necessary to know the mean relative molecular mass of the substance. An accurate and rapid method in BS 6829-3.1 consists of determining by gas-liquid chromatography (GLC) the mean relative molecular mass of the alkylbenzene used to manufacture the monosulfonated products.
The relative molecular mass of the respective monosulfonate or monosulfonic acid can then be calculated by adding the relative molecular mass of the SO3Na group minus Na, or that of the SO3H group minus H. BS 6829-3.1 provides you with the reagents, apparatus, material, and sampling required for the test method.
BS 6829-3.1 guides you with the procedure, examination of chromatograms and expression of results. BS 6829-3.1 helps you to determine the mean relative molecular mass by gas-liquid chromatography (GLC).
ISO 6841:1988