ISO INTERNATIONAL STANDARD 10136-5 First edition 1993-07-01 ANSI Internat Doc Sec Glass and glassware -- Analysis of extract solutions Part 5: Determination of iron(lll) oxide by molecular absorption spectrometry and flame atomic absorption spectrometry Verre et verrerie - Analyse des solutions d'attague Partie 5: Dosage de I'oxyde de ferl) par spectrometrie d'absorption moléculaire et par spectrométrie d'absorption atomique dans la flamme Referencenumber ISO10136-5:1993(E) r Standardizatior No reproduction or networking permited without license from IHS Not for Resale ISO 10136-5:1993(E) Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standardsbodies(lSOmemberbodies).Thework of preparing International Standards is normally carried out through IsO represented on that committee. international organizations, governmental and non-governmental, in liaison with isO, also take part in the work. IsO collaborates closelywiththeInternational Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. International Standard iSO 10136-5 was prepared by Technical Committee ISO/TC 48, Laboratory glassware and related apparatus, Sub-Committee SC 5, Quality of glassware. ISsO 10136 consists of the following parts, under the general titie Glass andglassware-Analysisofextractsolutions: Part 1: Determination of silicon dioxide by molecular absorption spectrometry Part 2: Determination of sodium oxide and potassium oxide by flame spectrometricmethods Part 3: Determination of calcium oxide and magnesium oxide by flame atomic absorption spectrometry - Part 4: Determination of aluminium oxide by molecular absorption spectrometry Part5:Determinationof iron(lll)oxidebymolecularabsorption spectrometry and flame atomic absorption spectrometry -Part6:Determination of boron(lll) oxide by molecular absorption spectrometry Annex A of this part of ISO 10136 is for information only. @ISO1993 by any means, electronic or mechanical, including photocopying and microfim, without per- mission in writing from the publisher. International OrganizationforStandardization Case Postale 56: CH-1211 Geneve 20· Switzerland Printed in Switzerland ISO10136-5:1993(E Introduction All silicate glasses contain some iron, although in very low concentrations, into a container, or when solutions are stored (even at ambient tempera- tures) for long periods of time. Iron may be released into the extract sol- utions produced during hydrolytic resistance tests and, because the concentration will be very low, a very sensitive test method is required for its determination. Technical Committee 2, Chemical Durability and Analysis, of the Inter national Commission on Glass (iCG), investigated the problem (see [6] in annex A) and considered flame-emission, flame atomic absorption and two molecular absorption spectrometric methods, using ortho-phenanthroline and bathophenanthroline. As a result of these delib- erations,itwasconsideredthatthebathophenanthrolinemethodprobably oratories participated in the round-robin study to develop recommended procedures using both molecular absorption and flame atomic absorption spectrometry The results of investigations on turbidities, especially in grain test sol- utions, showed that acidification to dissolve possible hydroxides and/or carbonates is necessary prior to the analytical determination. This is achieved by using spectroscopic buffer solutions, which are normally strongly acidic, or by addition of acids. Copyright Intemational Organization for Standardization ili Provided by IHS under license with Isc No reproduction or networking permited without license from IHS Not for Resale