Overview
ISO 893:1989 specifies standardized methods of analysis for technical alkane sulfonates, a class of surface active agents (surfactants). It applies to technical alkane sulfonates in powder, paste or liquid form and covers routine determinations used for quality control, specification and product release. The standard also includes informative annexes: a general scheme of analysis (Annex A) and a method for determination of total salts content (Annex B).
Key topics and requirements
The standard defines analytical procedures and reporting requirements for critical parameters of alkane sulfonates, including:
- pH measurement (on a 5% solution) - reference procedure: ISO 4316.
- Water content - Karl Fischer method for products <10% water (ISO 4317) and azeotropic distillation for products >5% water (ISO 4318).
- Free alkalinity / free acidity - titrimetric methods (ISO 4314).
- Matter extractable by light petroleum - extraction procedure referenced to ISO 1104.
- Total alkane sulfonate content - method by ISO 6122; Annex B provides a cross-check via total salts.
- Alkane monosulfonate content - ISO 6121 or ISO 6845 (direct two‑phase titration or alternate methods).
- Sodium sulfite, sulfate and chloride content - sulfite by ISO 1104 procedures, sulfate by ISO 6844, chloride by ISO 894.
- Sample preparation and dilution - prepare a laboratory sample (~300 g) and dilute so the technical alkane sulfonate content is about 20–30% (m/m); conversion of results back to raw-material basis is by the dilution factor.
- Test report requirements - identification of sample, reference to ISO 893:1989, methods used, results with units and any deviations or operational details.
Practical applications and users
ISO 893:1989 is intended for:
- Quality control laboratories in surfactant and detergent manufacturing.
- Raw-material suppliers and formulation chemists verifying alkane sulfonate content and impurities.
- Regulatory and compliance testing where standardized, reproducible analytical methods are required.
- R&D teams assessing product consistency, water content and salt balance in technical alkane sulfonates.
Using these harmonized methods helps ensure comparability between laboratories, accurate specification of sodium alkane sulphonates, and reliable detection of impurities (sulfite, sulfate, chloride) that affect performance and stability.
Related standards
ISO 893:1989 references and aligns with several ISO methods, including:
- ISO 4314, 4316, 4317, 4318, 607, 6844, 6845, 6121, 6122, 894, 1104.
These linked standards provide the detailed analytical techniques cited within ISO 893:1989.