ISO INTERNATIONAL STANDARD 9463 Third edition 2019-01 Nuclear energy Nuclear fuel technology Determination of plutonium in nitric acid solutions by spectrophotometry Energie nucleaire -Technologie du combustible nucléaire- Détermination du plutonium dans les solutions d'acide nitrique par spectrophotométrie Reference number IS0 9463:2019(E) so IS02019 IS0 9463:2019(E) COPYRIGHTPROTECTEDDOCUMENT @ ISO 2019 All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior written permission. Permission can be requested from either IsO at the address below or Iso's member body in the country of the requester. ISO copyright office CP 401 : Ch. de Blandonnet 8 CH-1214 Vernier, Geneva Phone: +4122 749 0111 Fax: +41 22 749 09 47 Email: [email protected] Website: www.iso.org Published in Switzerland ii @ IS0 2019 - All rights reserved IS0 9463:2019(E) Contents Page Foreword ..iv 1 Scope .1 2 Normative references .1 3 Terms and definitions 4 Principle ..1 5 Chemical conditions ..1 5.1 Stability of Pu(VI) .1 5.2 Rate of oxidation of Pu(IV) to Pu(VI) .2 5.3 Destruction of the excess oxidant .2 5.4 Comparison of Ce(IV) and Ag(II) .2 5.5 Molar extinction coefficient of Pu(VI) 2 6 Reagents. .3 6.1 General .3 6.2 Common reagents for methods using silver oxide or cerium as oxidant .3 6.3 Reagents for method using silver oxide as oxidant .3 6.4 Reagents for method using Ce(IV) as oxidant. .3 7 Apparatus. .4 8 Test procedure .4 8.1 Preparation of the different solutions. ..4 8.1.1 Plutonium calibration solution 4 8.1.2 Sample solutions .5 8.2 Spectrophotometer setup .6 8.3 Measurements .6 8.3.1 Background measurement .6 8.3.2 Measurements on the calibration solution 7 8.3.3 Measurements on the sample solution.. Expression of the result. 1 9 9.1 Calculation of the concentration of plutonium in the sample 1 9.2 Reproducibility ..8 9.3 Detection limit .8 10 Interferences .8 10.1 Anions. ..8 10.2 Cations .9 Annex A (informative) Preparation of silver (II) oxide (AgO) ..11 Bibliography .12 IS0 2019 - All rights reserved iii