ISO INTERNATIONAL STANDARD 16797 First edition 2004-04-15 Nuclear energy Soxhlet-mode chemical durability test Application to vitrified matrixes for high-level radioactive waste Energie nucléaire - Test de durabilité chimique en mode Soxhlet . Application aux matrices vitrifiees des déchets radioactifs de haute activite Reference number ISO 16797:2004(E) ISO @ISO 2004 ISO 16797:2004(E) PDF disclaimer This PDF file may contain embedded typefaces. In accordance with Adobe's licensing policy, this file may be printed or viewed but shall not be edited unless the typefaces which are embedded are licensed to and instailed on the computer performing the editing. In downloading this file, parties accept therein the responsibility of not infringing Adobe's licensing policy. The ISO Central Secretariat accepts no liability in this area. Adobe is atrademark of Adobe Systems Incorporated. Details of the software products used to create this PDF file can be found in the General Info relative to the file; the PDF-creation parameters were optimized for printing. Every care has been taken to ensure that the file is suitable for use by IsO member bodies. In the @ISO2004 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, ISO's member body in the country of the requester. ISO copyright office Case postale 56 · CH-1211 Geneva 20 Tel. + 41 22 749 01 11 Fax + 41 22 749 09 47 E-mail [email protected] Web www.iso.org Published in Switzerland @ ISO 2004 - All rights reserved ISO 16797:2004(E) Foreword IsO (the International Organization for Standardization) is a worldwide federation of national standards bodies technical committees. Each 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, governmental and Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. International Standards are drafted in accordance with the rules given in the ISO/lEC Directives, Part 2 The main task of technical committees is to prepare International Standards. 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. rights.ISOshallnotbeheldresponsibleforidentifyinganyorallsuchpatentrights. ISO 16797 was prepared by Technical Committee ISO/TC 85, Nuclear energy, Subcommittee SC 5, Nuclear fueltechnology. raanizationforsiandardization'ghtsreserved ISO 16797:2004(E) Introduction Any material submitted to the action of water is subject to alteration. Numerous leach tests have been developedtomeasurethisalteration.Oneofthese,theSoxhlettest,isroutinelyusedtoassessthechemical durability of nuclear glasses, and is now widely applied to other types of glass, to materials resulting from vitrification processes, or even to other nonporous solids intended for containment of non-radioactive toxic wastes. This is a short-term test designed to obtain a quick assessment of the chemical durability of a material in deionized water at about 10o °C. In a static environment without water renewal, the concentration of dissolved material in solution increases, and the alteration rate subsequently diminishes. Conversely, the maximum alteration rate is observed in continuously renewed deionized water, or in a complexing medium that consumes elements from solution and prevents saturation from occurring. conditions @ ISO 2004 - All rights reserved ISO 16797:2004(E) INTERNATIONALSTANDARD Nuclear energy Soxhlet-mode chemical durability test - Application to vitrified matrixes for high-level radioactive waste 1 Scope materials by measuring the initial dissolution rate in pure water. The measurement is performed at the boiling point of water, at which the dissolution rate is considerably higher than at r