BS ISO 8300-2013 Nuclear fuel technology Determination of plutonium content in plutonium dioxide of nuclear grade quality Gravimetric method《核燃料技术 核级二氧化钚中钚含量的测定 重量法》.pdf

1、BSI Standards Publication BS ISO 8300:2013 Nuclear fuel technology Determination of plutonium content in plutonium dioxide of nuclear grade quality Gravimetric methodBS ISO 8300:2013 BRITISH STANDARD National foreword This British Standard is the UK implementation of ISO 8300:2013. The UK participat

2、ion in its preparation was entrusted to Technical Committee NCE/9, Nuclear fuel cycle technology. A list of organizations represented on this committee can be obtained on request to its secretary. This publication does not purport to include all the necessary provisions of a contract. Users are resp

3、onsible for its correct application. The British Standards Institution 2013. Published by BSI Standards Limited 2013 ISBN 978 0 580 75790 7 ICS 27.120.30 Compliance with a British Standard cannot confer immunity from legal obligations. This British Standard was published under the authority of the S

4、tandards Policy and Strategy Committee on 31 December 2013. Amendments issued since publication Date Text affectedBS ISO 8300:2013 ISO 2013 Nuclear fuel technology Determination of plutonium content in plutonium dioxide of nuclear grade quality Gravimetric method Technologie du combustible nuclaire

5、Dtermination de la teneur en plutonium dans du dioxyde de plutonium de qualit nuclaire Mthode gravimtrique INTERNATIONAL STANDARD ISO 8300 Second edition 2013-12-15 Reference number ISO 8300:2013(E)BS ISO 8300:2013ISO 8300:2013(E)ii ISO 2013 All rights reserved COPYRIGHT PROTECTED DOCUMENT ISO 2013

6、All rights reserved. Unless otherwise specified, 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

7、 from either ISO at the address below or ISOs 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 copyrightiso.org Web www.iso.org Published in SwitzerlandBS ISO 8300:2013ISO 8300:2013(E) ISO 2013 All

8、 rights reserved iii Contents Page Foreword iv Introduction v 1 Scope . 1 2 Principle 1 3 Interferences 1 4 Apparatus . 1 5 Procedure. 2 5.1 Handling of the sample at the sampling station . 2 5.2 Tarring of crucibles . 2 5.3 Sub-sampling 2 5.4 Heating . 2 5.5 Additional measurements . 2 6 Expression

9、 of result . 3 6.1 Calculation of the gravimetric conversion factor 3 6.2 Calculation of impurity correction factor 3 6.3 Calculation of plutonium concentration . 3 6.4 Repeatability . 4 6.5 Systematic errors 4 7 Test report . 4 Annex A (informative) Gravimetric conversion factor for the non-volatil

10、e impurities .5BS ISO 8300:2013ISO 8300:2013(E) 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. Each m

11、ember 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 non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International

12、Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the different ty

13、pes of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives). Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not b

14、e held responsible for identifying any or all such patent rights. Details of any patent rights identified during the development of the document will be in the Introduction and/or on the ISO list of patent declarations received (see www.iso.org/patents). Any trade name used in this document is infor

15、mation given for the convenience of users and does not constitute an endorsement. For an explanation on the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISOs adherence to the WTO principles in the Technical Barriers to Trade (TBT) see t

16、he following URL: Foreword - Supplementary information The committee responsible for this document is ISO/TC 85, Nuclear energy, nuclear technologies, and radiological protection, Subcommittee SC 5, Nuclear fuel cycle. This second edition cancels and replaces the first edition (ISO 8300:1987), of wh

17、ich it constitutes a minor revision.iv ISO 2013 All rights reservedBS ISO 8300:2013ISO 8300:2013(E) Introduction The method specified in this International Standard is based on an oxidation of the plutonium followed by weighing. If the content of impurities is measured, a correction is made to allow

18、 for them. Respecting certain conditions, the overall standard deviation on a single determination (gravimetric determination and impurities correction) can be below 0,1 %. ISO 2013 All rights reserved vBS ISO 8300:2013BS ISO 8300:2013Nuclear fuel technology Determination of plutonium content in plu

19、tonium dioxide of nuclear grade quality Gravimetric method 1 Scope This International Standard specifies a precise and accurate gravimetric method for determining the plutonium content in plutonium dioxide (PuO 2 ) of nuclear grade quality, containing a mass fraction of less than 0,65 % of non-volat

20、ile impurities. The method is used to cross-check accountancy analyses of plutonium dioxide. 2 Principle The method specified in this International Standard consists of the following: a) sampling and weighing of the sample in dry atmosphere; b) heating in air between 1 200 C and 1 250 C to constant

21、mass in order to obtain a stoichiometric plutonium dioxide, which is stable and non-hygroscopic; c) weighing of the plutonium dioxide; d) impurity analysis and correction for non-volatile impurities; e) calculation of plutonium concentration; f) calculation of the plutonium content using a gravimetr

22、ic conversion factor which depends slightly on the isotopic composition of the plutonium. If the latter is not known, it shall be measured, usually by mass spectrometry. 3 Interferences All impurities which are not volatile at 1 200 C cause a positive bias in the analysis. Their actual content shall

23、 be measured with appropriate techniques, including, for example, atomic emission or absorption spectroscopy. If the total non-volatile impurities content is of a mass fraction of up to 0,1 %, the overall uncertainty of the measurement will depend on the precision of the impurities determination. 4

24、Apparatus 4.1 Sub-sampling station, comprising a glove box under dry atmosphere (dew point less than or equal to 40 C) equipped with an analytical balance accurate to 0,1 mg. 4.2 Heating box, supplied with ambient air and equipped with a temperature-regulated muffle furnace capable of operating at 1

25、 200 C to 1 250 C. 4.3 Stainless steel sampling vials. 4.4 Platinum crucibles. INTERNATIONAL ST ANDARD ISO 8300:2013(E) ISO 2013 All rights reserved 1BS ISO 8300:2013ISO 8300:2013(E) 4.5 Desiccators. 5 Procedure 5.1 Handling of the sample at the sampling station 5.1.1 Transfer at least 10 g of the m

26、aterial to be analysed into a vial (4.3). 5.1.2 Hermetically seal the vial. 5.1.3 Transfer the vial rapidly to the sub-sampling station (4.1). 5.2 Tarring of crucibles 5.2.1 Heat a clean crucible (4.4) for 1 h at 1 200 C to 1 250 C. Cool for 20 min in the desiccators (4.5) and then for 5 min in the

27、balance (4.1 a), weigh to within 0,1 mg. Repeat the heating until the mass remains constant to within 0,1 mg. 5.2.2 Record the constant mass, m 1 , to an accuracy of 0,1 mg. 5.3 Sub-sampling 5.3.1 As soon as possible after receiving the vial containing the sample, transfer about 1,5 g of the sample

28、into the tarred crucible. 5.3.2 Measure and record the gross mass of the crucible, m 2 , to an accuracy of 0,1 mg. 5.3.3 If several sub-samples are taken, keep the first in the sub-sampling station and weigh it again after all the sub-samples have been taken. 5.3.4 If the change in mass of the first

29、 sub-sample is less than 0,1 mg, transfer the sub-samples to the heating box (4.2). If this is not the case, discard the sub-samples, adjust the hygrometry of the box, and repeat the sampling and the procedure. 5.4 Heating 5.4.1 Heat the 1,5 g sample for 1 h at 1 200 C to 1 250 C. 5.4.2 Cool for 20

30、min in the desiccators and weigh it to within 0,1 mg. 5.4.3 Repeat 5.4.1 and 5.4.2 until the mass remains constant to within 0,1 mg. 5.4.4 Record the new gross mass, m 3 , to an accuracy of 0,1 mg. 5.5 Additional measurements 5.5.1 Perform an isotopic analysis of plutonium to calculate its mean rela

31、tive atomic mass, A r (Pu). 5.5.2 Perform an analysis of the impurities that are not volatile at 1 200 C.2 ISO 2013 All rights reservedBS ISO 8300:2013ISO 8300:2013(E) 6 Expression of result 6.1 Calculation of the gravimetric conversion factor Calculate the gravimetric conversion factor using Formul

32、a (1). (1) where A r (O) = 15,9994 is the relative atomic mass of oxygen; A r (Pu) is the mean relative atomic mass of plutonium calculated using Formula (2). (2) where m 238 , m 239 , etc are the mass fractions of the plutonium isotopes 238 Pu, 239 Pu, etc. in the samples. 6.2 Calculation of impuri

33、ty correction factor Express the results of the impurity analyses in micrograms of each impurity element per gram of the original sample (I n ). Calculate the total mass of impurities, I o , in grams, in the heated sample using Formula (3). (3) where m 2 m 1 is the mass of the sample before heating;

34、 m 2 is the gross mass before heating, in grams (sample plus crucible); m 1 is the mass of the crucible, in grams; I n is the mass of impurity element n, in micrograms per gram of the original sample; C n is the gravimetric conversion factor for element n (see Annex A). NOTE Depending on the context

35、 in which the results are to be used, mass (m 2m 1 ) can require standard corrections for air buoyancy effects. 6.3 Calculation of plutonium concentration Calculate the plutonium concentration, Pu, as a percentage, in the sample using Formula (4). (4) where m 3 is the gross mass after heating (sampl

36、e plus crucible), in grams. ISO 2013 All rights reserved 3BS ISO 8300:2013ISO 8300:2013(E) 6.4 Repeatability The standard deviation for a single gravimetric determination is about 0,05 %. In order for the standard deviation of the impurity correction factor to stand below 0,1 %, the impurities shall

37、 be measured to the following: with a standard deviation of 50 % (detection limit) up to 1 000 g g 1of impurities; with a standard deviation of 25 % (semiquantitative analysis) up to 2 500 g g 1of impurities; with a standard deviation of 10 % (quantitative analysis) up to 6 500 g g 1of impurities. I

38、n these conditions, the overall standard deviation on a single determination (gravimetric determination and impurities correction) is below 0,1 %. 6.5 Systematic errors 6.5.1 The systematic errors due to weighing have a coefficient of variation no greater than 0,014 %. 6.5.2 Non-stoichiometry of the

39、 plutonium oxide is a potential systematic error or bias; the coefficient of variation of this factor is expected to be less than 0,1 %. 6.5.3 Non-volatile impurities are responsible for three further possible sources of bias: a) calibration errors in the impurity analysis; b) uncertainties in the i

40、mpurity conversion factors; c) the impurities that are not corrected for, because they are neither measured nor detected, are a source of positive bias. These sources can cause a systematic error of up to 20 % of the total impurity concentration. 7 Test report The test report shall include the follo

41、wing information: a) identification of the sample; b) reference of the method used; c) results of the measurement and the associated overall uncertainties, impurities percentage, and method of expression used; d) unusual features noted during the test; e) operations not included in this Internationa

42、l Standard (i.e. ISO 8300).4 ISO 2013 All rights reservedBS ISO 8300:2013ISO 8300:2013(E) Annex A (informative) Gravimetric conversion factor for the non-volatile impurities Table A.1 Gravimetric conversion factor for the non-volatile impurities Impurity Probable shape of the impurity Conversion fac

43、tor C n Ag Ag 1,00 Al Al 2 O 3 1,89 Am AmO 2 1,13 B B 2 O 3 3,22 Ba BaO 1,12 Be BeO 2,78 Bi Bi 2 O 3 1,11 Ca CaO 1,40 Cd Cd 1,00 Co CoO 1,27 Cr Cr 2 O 3 1,46 Cu Cu 1,00 Fe Fe 3 O 4 1,38 K K 2 O 1,21 Mg MgO 1,66 Mn Mn 3 O 4 1,39 Na Na 2 O 1,35 Ni Ni 2 O 3 1,40 P P 2 O 5 2,29 Pb PbO 1,07 Rare earth M

44、2 O 3 1,16 Sb Sb 2 O 3 1,20 Si SiO 2 2,14 Sn SnO 1,13 Ta Ta 2 O 5 1,22 Th ThO 2 1,14 Ti TiO 2 1,67 V V 2 O 5 1,78 W WO 3 1,26 ISO 2013 All rights reserved 5BS ISO 8300:2013ISO 8300:2013(E) Impurity Probable shape of the impurity Conversion factor C n Zn ZnO 1,24 Zr ZrO 2 1,35 NOTE This information i

45、s deduced from the most reliable available information, taking into account the calcinations and the cooling conditions and the matrices effects due to plutonium oxide. The chemical shape of the impurities is not well known and, consequently, the maximum amount of impurities is fixed at 0,65 % of th

46、e Pu mass.Table A.1 (continued) 6 ISO 2013 All rights reservedBS ISO 8300:2013BS ISO 8300:2013ISO 8300:2013(E) ISO 2013 All rights reserved IC S 27.120.30 Price based on 6 pagesThis page deliberately left blankBSI is the national body responsible for preparing British Standards and other standards-r

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