2829 NTERNATIONAL STANDARD (Tso INTERNATIONAL ORGANIZATION FOR STANDARDIZATION MEXIyHAPOHAH OPrAHW3ALWS HIO CTAHIAPTH3ALIWW.ORGANISATION INTERNATIONALE DE NORMALISATION Aluminium oxide primarily used for the production of aluminium --- Determination of phosphorus content - Reduced phosphomolybdate spectrophotometric method First edition - 1973-12-15 UAN1E AsT Tmtarmcut De UDC 661.862.22 : 546.18 : 543.42 Ref. No. 1SO 2829-1973 (E) Descriptors : aluminium oxide, chemical analysis, determination of content, phosphorus, spectrophotometry. Price based on 3 pages nsefromIHS 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, aiso 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. ISO/TC 47, Chemistry, and circulated to the Member Bodies in June 1972. It has been approved by the Member Bodies of the following countries : Australia India South Africa, Rep. of Austria Ireland Sweden Belgium Italy Switzerland Canada Morocco Thailand Czechoslovakia Netherlands Turkey France Poland United Kingdom Germany Portugal U.S.S.R. Hungary Romania This International Standard has also been approved by the International Union of Pure and Applied Chemistry (IUPAC). The Member Body of the following country expressed disapproval of the document on technical grounds : New Zealand @ International Organization for Standardization, 1973 : Printed in Switzerland Copyright International Organization for Standardization Not for Resale se from IHS INTERNATIONAL STANDARD ISO 2829-1973 (E) Aluminium oxide primarily used for the production of aluminium - Determination of phosphorus content - Reduced phosphomolybdate spectrophotometric method 1 SCOPE AND FIELD OF APPLICATION 4.5 Sulphuric acid, approximately 10 N solution. This International Standard specifies a spectrophotometric Carefully add, in small portions, 280 ml of sulphuric acid, method using reduced ammonium phosphomolybdate for p approximately 1,84 g/mi, about 96 % (m/m) solution, to the determination of the phosphorus content of aluminium about 500 mi of water and, after cooling, dilute to oxide primarily used for the production of aluminium. 1 000 ml. The method is applicable to phosphorus contents, 4.6 Sulphuric acid, approximately N solution. expressed as P205, greater than 0,000 5 %. Take 100 ml of the sulphuric acid solution (4.5) and ditute with water to 1 000 ml. 2 REFERENCE ISO/R 804, Aluminium oxide primarily used for the 4.7 Sulphuric acid, approximately 0,5 N sotution. production of aluminium - Preparation of sample solution Take 250 mi of the sulphuric acid solution (4.6) and dilute for analysis. with water to 500 ml. 4.8 Ammonium acetate, 500 g/l solution. 3 PRINCIPLE Preparation of a solution from a test portion by alkaline 4.9 Iron(lll) sulphate, acid solution. fusion, either with a mixture of sodium carbonate and boric acid, or with a mixture of sodium carbonate and sodium Dissolve O,5 g of iron(lll) sulphate nonahydrate tetraborate. Dissolution of the melt in nitric acid and [Fe2(SO4]3.9H2O] in 50 ml of water containing 2 ml of adjustment of an appropriate aliquot portion to pH 2. perchloric acid solution, p approximately 1,60 g/ml, about 64,5 % (m/m) solution, and dilute to 100 ml. Formation of the phosphomolybdic complex and extraction by 2-methylpropan-1-ol in a sulphuric acid medium. 1 ml of this solution contains about 0,001 g of Fe(1ll) Reduction of the complex by tin(ll) chloride in the organic NOT