NTERNATIONAL STANDARD (TSO) 4 4047 INTERNATIONAL ORGANIZATION FOR STANDARDIZATION MEKIYHAPOIHAS OPIAHW3ALIW HO CTAHIAPTW3AIWW.ORGANISATION INTERNATIONALE DE NORMALISATION Leather -- Determination of sulphated total ash and sulphated water-insoluble ash Cuir -- Dosage des cendres sulfatées totales et des cendres sulfatees insolubles dans I'eau First edition - 1977-11-01 O4047-1977 (E) Ref. No. 1SO 4047-1977 (E) UDC 675 : 543.82 Descriptors : leather, chemical analysis, determination of content, ash, mineral matter, sulphating analysis. Price based on 2 pages IsefromIHS Not for Resale FOREWORD ISO (the International Organization for Standardization) is a worldwide federation of 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-governmental, 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 Council. Standard ISO 4047 was developed by Technical Committee International ISO/TC 120, Leather, and was circulated to the member bodies in July 1976. It has been approved by the member bodies of the following countries : Hungary Australia Poland Brazil India Romania Iran South Africa, Rep. of Canada Chile Israel Turkey Italy Czechoslovakia United Kingdom Egypt, Arab Rep. of Mexico Yugoslavia France Netherlands Germany New Zealand No member body expressed disapproval of the document. This International Standard is based on method IUC/7 of the International Union of Leather Technologists' and Chemists' Societies. @ International Organization for Standardization, 1977 Printed in Switzerland Copyright International Organization for Standardization Not for Resale efrom IHS ISO 4047-1977 (E) INTERNATIONAL STANDARD Leather -- Determination of sulphated total ash and sulphated water-insoluble ash O INTRODUCTION 3 DEFINITIONS For the purposes of this International Standard, the The amount of mineral substances found by ashing leather following definitions apply : may differ fromthe actual content owingto decomposition, reduction, or the escape by volatilization of certain salts. 3.1 sulphated total ash : The residue obtained from By treating the ash with sulphuric acid, the salts and oxides carbonized leather at 800 °C after suiphating the ash under are converted into sulphates, but some salts will again be the specified conditions. transformed into oxides at the selected temperature of ignition. 3.2 sulphated water-insoluble ash : The residue obtained To determine the total mineral content, for exampie within when leather,previously extracted with water as specified the framework of a complete leather analysis, the water- in ISO 4098, is carbonized after sulphating the ash under soluble and water-insoluble inorganic substances can be the specified conditions. ascertained by calculation or determined separately. Ammonium salts are not determined by this method 4 PRINCIPLE (compare with IS0 4098). Carbonization of the leather followed by treatment with sulphuric acid and ashing in an open crucible 1 SCOPE AND FIELD OF APPLICATION This International Standard specifies a method for the determination of the sulphated total ash and the sulphated 5 REAGENTS water-insoluble ash of leather. During the analysis, use only reagents of recognized The method is applicable to all types of leather. analytical grade and only distilled water or water of equivalent purity. The determination may be inaccurate by the extent to which the leather contains organo-metallic compounds, 5.1 Sulphuric acid, approximately 2 N solution. for example silicone (see note 1 in 8.1). 5.2 Ammonium nitrate, approximately 100 g