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STANDARD
SIST EN 27520:2009
SIST EN 27520:2009
SIST EN 27520:2009
International Standard INTERNATIONAL ORGANIZATION FOR STANDARDIZATION.MEX~YHAPOAHAR OPI-AHM3AUMR fl0 CTAH,QAPTM3ALWl~ORGANISATION INTERNATIONALE DE NORMALISATION Ferronickel - Determination of Cobalt content - Flame atomic absorption spectrometric method Ferro-nicke1 - Dosage du Cobalt - Mhthode par spectromhrie d’absorption atomique dans Ia flamme First edition - 1985-11-15 UDC 669.243.881: 543.422 : 546.73 Ref. No. ISO 75204985 (E) Descriptors : nickei, ferronickel, Chemical analysis, determination of content, Cobalt, atomic absorption method. Price based on 3 pages SIST EN 27520:2009
Foreword ISO (the International Organization for Standardization) is a worldwide federation of national Standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Esch member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, govern- mental 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. They are approved in accordance with ISO procedures requiring at least 75 % approval by the member bodies voting. International Standard ISO 7520 was prepared by Technical Committee ISO/TC 155, Nickel and nicke/ alfoys. Users should note that all International Standards undergo revision from time to time and that any reference made herein to any other International Standard implies its latest edition, unless othennlise stated. 0 International Organkation for Standardkation, 1985 Printed in Switzerland SIST EN 27520:2009
INTERNATIONAL STANDARD ISO 75204985 (E) Ferronickel - Determination of Cobalt content - Flame atomic absorption spectrometric method 1 Scope and field of application This International Standard specifies a flame atomic absorption spectrometric method for the determination of the Cobalt con- tent of ferronickel in the range 0,025 to 2,5 % (mlm). 2 References ISO 385/1, Laborstory glassware - Burettes - Part 1: General requiremen ts. ISO 648, Laboratory glassware - One-mark pipettes. ISO 1042, Laborstory glassware - One-mark volumetric flasks. ISO 5725, Precision of test methods - Determination of repea tabiWy and reproducibility by in ter-labora tory tests. ISO 6352, Ferronickel - Determination of nicke/ tonten t - Dimethylglyoxime gravimetric method. 3 Principle Dissolution of a test Portion in a nitric acid-hydrochloric acid mixture. Precipitation of silica by dehydration in perchloric acid. Removal of silica by filtration. Addition of lanthanum for elimination of potential interferences. Determination of Cobalt by atomic absorption spectrometry in an air-acetylene flame at a wavelength of 240,7 nm. NOTE - This analysis tan be carried out on solutions which have been used for the determination of nicke1 by ISO 6352. 4 Reagents During the analysis, use only reagents of recognized analytical grade and only distilled water or water of equivalent purity. 4.1 Hydrochlorit acid, 020 = 1,19 g/ml. 4.2 Hydrochlorit acid, ~20 = 1,19 g/ml, diluted 1+9. 4.3 Nitrit acid, 020 = 1,41 g/ml, diluted 1 + 1. 4.4 Perchlorit acid, ~20 = 1,61 g/ml [72 % (mlm)]. 4.5 Hydrofluoric acid, ~2~ = 1,14 g/ml, diluted 1 + 1. WARNING - Hydrofluoric acid is extremely irritating and corrosive to skin and mucous membranes, producing severe skin burns which are slow to heal. In case of skin contact wash weil with water and seek medical advice. 4.6 Lanthanum, Solution, containing 200 g of La per litre. Weigh 250 g of lanthanum chloride hexahydrate ( LaC13m 6H2O) and transfer to a 600 ml beaker. Add 25 ml of hydrochloric acid (4.1) and 300 ml of water. Stir to complete dissolution. Filter, if necessary, into a 500 ml one-mark volumetric flask, make up to the mark with water and mix. 4.7 Nickel plus iron, matrix Solution, containing 12 g of Ni and 28 g of Fe per Iitre. 4.7.1 Weigh 12,0 g of high purity nicke1 powder [containing less than 0,001 % (mlm) Cobalt] into an 800 ml beaker. Add 50 ml of water and 50 ml of nitric acid (pzo = 1,41 g/ml). When the initial reaction subsides, stir and heat to complete dissolu- tion. Dilute to about 250 ml with water. 4.7.2 Weigh 28,0 g of high purity iron powder [containing less than 0,001 % (mhd Cobalt1 into an 800 ml beaker. Add 100 ml of hydrochloric acid diluted 1 + 1. Carefully add 50 ml of nitric acid (920 = 1,41 g/ml) and heat to complete dissolution and Oxidation of iron. Dilute to about 250 ml. 4.7.3 Carefully combine the nicke1 Solution (4.7.1) with the iron Solution (4.7.2). Filter into a 1 000 ml one-mark volumetric flask, make up to the mark with water and mix. 4.8 Cobalt, Standard Solution, corresponding to 0,500 g of Co per litre. Weigh, to the nearest 0,001 g, 0,500 g of high purity [99,9 % (mlm) Co, minimuml Cobalt powder, transfer to a 600 ml beaker and add 40 ml of nitric acid (4.3). Heat to complete dissolution, boil gently to expel oxides of nitrogen, cool and transfer to a 1 000 ml one-mark volumetric flask containing 160 ml of nitric acid (4.3). Make up to the mark with water and mix. 1 ml of this Standard Solution contains 0,500 mg of Co. SIST EN 27520:2009
ISO 75204985 (EI 5 Apparatus Ordinary laboratory glassware, and 5.1 Atomic absorption spectrometer, equipped with a laminar flow burner for an air-acetylene flame and a Cobalt hollow cathode lamp. 5.2 Burette, of capacity 50 ml, graduated in divisions of 0,l ml, in accordance with ISO 385/1, class A. 5.3 Glass beakers, of capacity 600 ml, clean, unetched and flat bottomed. 5.4 Pipettes, of capacities 25 and 50 ml, in accordance with ISO 648, class A. 5.5 Volumetric flasks, of capacities 250; 500; and 1 000 ml, in accordance with ISO 1042, class A. 5.6 Polytetrafluoroethylene (PTFE) beaker, of capacity 600 ml, for samples with a high Silicon content. 6 Sampling and samples 6.1 Sampling and preparation of the laboratory Sample shall be carried out by normal agreed procedures or, in case of dispute, by the relevant International Standard. 6.2 The laboratory Sample normally is in the form of millings, drillings or granules and no further preparation of the Sample is necessary. 6.3 If it is suspected that the laboratory Sample is con- taminated with oil or grease from the milling or drilling process, it shall be cleaned by washing with high purity acetone and dry- ing in air. 6.4 If the laboratory Sample contain
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