2868 NTERNATIONAL STANDARD ( SO) INTERNATIONAL ORGANIZATION FOR STANDARDIZATION MEXIYHAPOIHAH OPTAHW3ALW HIO CTAHIAPTW3ALIWW.ORGANISATION INTERNATIONALE DE NORMALISATION Surface active agents - Detergents - Anionic-active matter stable to acid hydrolysis -- Determination of trace amounts First edition - 1973-12-01 ov 1 3 U vSi Interci Doc Sect ISO 2868-1973 (E) UDC 661.185 : 543 Ref. No. ISO 2868-1973 (E) Descriptors : surfactants, detergents, chemical analysis, determination of content, anionic-active matter, volumetric analysis, acid conditions Price based on 2 pages Notfor Resale FOREWORD iso (the International Organization for Standardization) is a worldwide federation Fof national standards institutes (ISO Member Bodies). The work of developing 'International Standards is carried out through isO Technical Committees. Every Member Body interested in a subject for which a Technical Committee has been set up has the right to be represented on that Committee. International organizations, governmental and non-governmentat, in liaison with isO, also take part in the work. Draft International Standards adopted by the Technical Committees are circulated to the Member Bodies for approval before their acceptance as International Standards by the ISO Councit. International Standard ISO 2868 was drawn up by Technical Committee ISO/TC91, Surface active agents, and circulated to the Member Bodies in August 1972. Austria Ireland Spain Belgium Japan Switzerland Egypt, Arab Rep. of Mexico Thailand France New Zealand Turkey Germany Poland United Kingdom Hungary Romania U.S.A. India South Africa, Rep. of U.S.S.R. This International Standard has also been approved by the International Union of Pure and Applied Chemistry (IUPAC). No Member Body expressed disapproval of the document. @ International Organization for Standardization, 1973 Printed in Switzerland Copyright International Organization for Standardization Not for Resale ISO 2868-1973 (E) INTERNATIONAL STANDARD Surface active agents -- Detergents - Anionic-active matter stable to acid hydrolysis - Determination of trace amounts 1 SCOPE 5.4 Sodium hydroxide, 1,0 N standard volumetric solution. This Internationa! Standard specifies a method for the determination of small quantities of stable anionic-active 5.5 Sodium iauryl sulphate, 0,004 M standard volumetric matter present in detergents, in the presence of a large solution. excess of hydrolyzable anionic-active matter which will hydrolyze under conditions of acid reflux. 5.6 Benzethonium chloride, 0,004 M standard volumetric solution. 2 FIELD OF APPLICATION 5.7 Phenolphthalein solution. This method is applicable to the determination of cyclic sulphonates in alkylphenol ether sulphates and of smali 5.8 Mixed indicator solution. amounts of sulphonates in sulphated fatty alcohols. The following reagents are necessary : The molar mass of the anionic-active matter must be known or previously determined, if its content is expressed as a 5.9 Sulphuric acid, 2 N solution. percentage by mass. 5.10 Sodium hydroxide, 10 N solution. 3 REFERENCE 5.11 Sodium hydroxide, 1 N solution. isO 2271, Surface active agents - Detergents -- Determi nation of anionic-active matter (direct two-phase titration procedure). 6 APPARATUS Ordinary laboratory apparatus, and 4 PRINCIPLE 6.1 Conical flask, 250 ml, with a conical ground glass Hydrolysis, by refluxing under acid conditions, of joint. anionic-active matter. 6.2 Reflux condenser, water-cooled, with a conical ground Determination of non-hydrolyzable anionic-active matter glass joint at the bottom. by the direct two-phase titration procedure described in ISO 2271. 7 PROCEDURE 5 REAGENTS 7.1 Test portion The water used shall be distillied water or water of at least Weigh, to the nearest 1 mg, a quantity of sample containing equivalent purity. between 0,5 and 2 g of anionic-active matter to be In addition to the reagents mentioned in ISO 2271 and subjected to hydrolysis, into the conical flask (6.1). given