ISO INTERNATIONAL STANDARD 9035 First edition 1989-08-15 Iron ores -- Determination of acid-soluble iron(ll) content -- Titrimetric method Minerais de fer -- Dosage du fer(ll soluble dans I'acide -- Methode titrimétrique Reference number ISO9035:1989 (E) Standardizatior Noreproductionor networking permitted without li nse from IHS Not for Resale ISO9035:1989(E) Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (IsO member bodies). The work of preparing International StandardsisnormallycarriedoutthroughIsotechnicalcommittees.Eachmember 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. iso collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. 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 International Standard ISO 9035 was prepared by Technical Committee ISO/TC 102, Ironores. Annex A forms an integral part of this International Standard. Annexes B and C are for information only. ? ISO1989 All rights reserved. No part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from thepublisher. International Organization for Standardization Not fr Resale ISO 9035 : 1989 (E) INTERNATIONAL STANDARD Iron ores - Determination of acid-soluble iron(ll) content -- Titrimetric method 1 Scope 3Principle ThisInternational Standardspecifiesa methodforthedetermi- Dissolution with hydrochloric acid in an inertatmosphere,addi- nation of iron(ll) content in natural and processed iron ores tion of a mixture of sulfuric and phosphoric acid and dilution containingfrom1%to25%acid-solubleiron(ll)andonlytra- with water. Determination of the iron(ll) content by titration cesofmetalliciron.Thismethodisspecificallylimitedforusein with potassium dichromate standard solution using sodium conjunction with the reducibility test methods specified in diphenylaminesulfonate as indicator. ISO 4695or ISO7215. This method is not applicable to ores containing more than 4 Reagents 0,3.% (m/m) sulfur (as sulfide) and/or5 % (m/m) free carbon. Experimentshaveshownthattheacid-insolubleresiduecanbe During the analysis, use only reagents of recognized analytical neglected, espeoially as regards the needs of the reducibility grade, and only distlled water or water of equivalent purity. testmethodsconcernedandtheprecisionobtainable NOTE - The water used for the procedure shouid be de-oxygenated by boiling. 2 Normative references 4.1 Sodium carbonate (Na2CO3) or sodium hydrogen The following standardscontainprovisionswhich,through carbonate (NaHCO3). referenceinthistextconstituteprovisionsofthisInternational Standard. At the time of publication, the editions indicated 4.2.Hydrochloric acid, g 1,16 g/ml to 1,19 g/ml. werevalid.All standards are subject to revision, and parties to agreements based on this International Standard are encour- NOTE -- This reagent should be de-oxygenated by purging with either aged to investigate the possibility of applying the most recent nitrogen or argon, or by heating for a short time. editions of the standiards isted beiow. Miembers of iEC and iSO maintain registers of currently valid International Standards. 4.3 Hydrofiuoric acid, 40 % (m/m), g 1,13 g/ml or Is0 385-1 : 1984, Laboratory glassware - Burettes - Part 1 : 48 % (m/ m), @ 1,16 g/ml. General requirements. 4.4 Sodium carbonate or sodium hydrogen carbonate. ISo 4695 : 1984, Iron ores - Determination of reducibility. saturated solution, at ambient temperature. Iso 4791-1 : 1985, Laboratory apparatus -- Vocabulary r