OSI 6374 International Standard INTE RNATIONAL ORGANIZATION FOR STANDARDIZATION MEXAYHAPOAHAH OPrAHW3ALWA NO CTAHAAPTW3ALWM-ORGANISATION INTE RNATIONALE DE NORMALISATION ANst Tterr Do Sec Cryolite, natural and artificial, and aluminium fluoride for industrial use -- Determination of phosphorus content -- Atomic absorption spectrometric method after extraction Cryolithe, naturelle et artificielle, et fluorure d'aluminium a usage industriel -- Dosage du phosphore -- Methode par spectrometrie d'absorption atomique apres extraction First edition --. 1981-10-15 UDC 661.862 + 553.634 : 543.422 : 546.18 Ref. No. ISO 6374-1981 (E) Descriptors : metal industry, aluminium ores, tests, determination of content, phosphorus, atomic absorption spectroscopic analysis. Price based on 4 pages Copyright International Organization for Standardization e from IHS Not for Re Foreword Iso (the International Organization for Standardization) is a worldwide federation of national standards institutes (IsO member bodies). The work of developing Inter- national Standards is carried out through ISso 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. International Standard ISO 6374 was developed by Technical Committee ISO/TC 47, Chemistry, and was circulated to the member bodies in May 1980. It has been approved by the member bodies of the following countries : Philippines Australia Germany, F. R. Austria Hungary Poland Belgium India Romania Brazil Ireland South Africa, Rep. of China Italy Switzerland Czechoslovakia Korea, Rep. of United Kingdom Mexico Egypt, Arab Rep. of USSR France Netherlands No member body expressed disapproval of the document. International Organization for Standardization,1981 Printed in Switzerland Copyright International Organization for Standardization sefrom IHS Not for Resale INTERNATIONAL STANDARD ISO 6374-1981 (E) Cryolite, natural and artificial, and aluminium fluoride for industrial use - Determination of phosphorus content - Atomic absorption spectrometric method after extraction Scope and field of application 4.6 Perchloric acid, approximately 200 g/l solution. This international Standard specifies an atomic absorption Dilute 87 ml of perchloric acid, g 1,68 g/ml, approximately spectrometric method, after extraction, for the determination 70 % (m/m) solution, to 500 ml. of the phosphorus content of natural and artificial cryolite and of aluminium fluoride for industrial use. 4.7 Phosphorus, standard solution corresponding 1,000 g of P per litre. The method is applicable to products having phosphorus con. tents, expressed as P205, in the range 5 to 60 mg/kg. Weigh, to the nearest 0,000 1 g, 4,393 6 g of potassium dihydrogenorthophosphate (KH2PO4) and dissolve in a little water. Transfer the solution quantitatively to a 1 000 ml one- 2 References mark volumetric flask, dilute to the mark and mix. ISo 1619, Cryolite, natural and artificial Preparation and 1 ml of this standard solution contains 1 mg of P. storage of test samples. 4.8 Phosphorus, .standard solution corresponding ISO 2925, Aluminium fluoride for industrial use - Preparation 0,050 g of P per litre. and storage of test samples. Place 50,0 ml of the standard phosphorus solution (4.7) in a 1 000 ml one-mark volumetric flask, dilute to the mark and mix. 3 Principle 1 ml of this standard solution contains 50 μg of P. Fusion of a test portion with sodium carbonate and boric acid and dissolution in perchloric acid solution. Formation of the Store this solution in a suitable plastics flask. ammonium molybdophosphate complex and extraction of the complex with iso