1、BSI Standards PublicationBS ISO 15247:2015Zinc sulfide concentrates Determination of silvercontent Acid dissolutionand flame atomic absorptionspectrometric methodBS ISO 15247:2015 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of ISO 15247:2015.The UK participation i
2、n its preparation was entrusted to TechnicalCommittee NFE/36, Copper lead and zinc ores and concentrates.A list of organizations represented on this committee can beobtained on request to its secretary.This publication does not purport to include all the necessaryprovisions of a contract. Users are
3、responsible for its correctapplication. The British Standards Institution 2015. Published by BSI StandardsLimited 2015ISBN 978 0 580 81813 4ICS 73.060.99Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of theStand
4、ards Policy and Strategy Committee on 30 June 2015.Amendments issued since publicationDate Text affectedBS ISO 15247:2015 ISO 2015Zinc sulfide concentrates Determination of silver content Acid dissolution and flame atomic absorption spectrometric methodConcentrs sulfurs de zinc Dosage de largent Mth
5、ode par dissolution acide et spectromtrie dabsorption atomique dans la flammeINTERNATIONAL STANDARDISO15247Second edition2015-07-01Reference numberISO 15247:2015(E)BS ISO 15247:2015ISO 15247:2015(E)ii ISO 2015 All rights reservedCOPYRIGHT PROTECTED DOCUMENT ISO 2015, Published in SwitzerlandAll righ
6、ts 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 from ei
7、ther ISO at the address below or ISOs member body in the country of the requester.ISO copyright officeCh. de Blandonnet 8 CP 401CH-1214 Vernier, Geneva, SwitzerlandTel. +41 22 749 01 11Fax +41 22 749 09 47copyrightiso.orgwww.iso.orgBS ISO 15247:2015ISO 15247:2015(E)Foreword iv1 Scope . 12 Normative
8、references 13 Principle 14 Reagents 15 Apparatus . 26 Samples 36.1 Test sample . 36.2 Test portion 37 Procedure. 37.1 Number of determinations . 37.2 Blank test . 37.3 Decomposition of test portion . 37.4 Determination of silver 48 Expression of results 49 Precision . 59.1 Expression of precision .
9、59.2 Method for obtaining the final result (see Annex B) 59.3 Precision between laboratories 59.4 Check of trueness 610 Test reports 7Annex A (normative) Procedure for the preparation and determination of the mass of a predried test portion . 8Annex B (normative) Flowsheet of the procedure for the a
10、cceptance of analytical values for test samples 10Annex C (informative) Derivation of precision equations .11Bibliography .15 ISO 2015 All rights reserved iiiContents PageBS ISO 15247:2015ISO 15247:2015(E)ForewordISO (the International Organization for Standardization) is a worldwide federation of n
11、ational standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO 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. Inter
12、national organizations, governmental 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 procedures used to develop this document and those inte
13、nded for its further maintenance are described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the different types 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
14、.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 be held responsible for identifying any or all such patent rights. Details of any patent rights identified during the development of the document w
15、ill 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 information given for the convenience of users and does not constitute an endorsement.For an explanation on the meaning of ISO specific terms and expres
16、sions related to conformity assessment, as well as information about ISOs adherence to the WTO principles in the Technical Barriers to Trade (TBT) see the following URL: Foreword - Supplementary informationThe committee responsible for this document is ISO/TC 183, Copper, lead, zinc and nickel ores
17、and concentrates.This second edition cancels and replaces the first edition (ISO 15247:1999), of which the warning in A.3.1 in Annex A has been revised.iv ISO 2015 All rights reservedBS ISO 15247:2015INTERNATIONAL STANDARD ISO 15247:2015(E)Zinc sulfide concentrates Determination of silver content Ac
18、id dissolution and flame atomic absorption spectrometric method1 ScopeThis International Standard specifies an acid dissolution and flame atomic absorption spectrometric method for the determination of silver content of zinc sulfide concentrates.The method is applicable to the determination of silve
19、r in zinc sulfide concentrates containing up to 60 % (m/m) zinc in the form of zinc blende and related materials.The method is applicable to silver contents from 10 g/t to 500 g/t.2 Normative referencesThe following documents, in whole or in part, are normatively referenced in this document and are
20、indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.ISO 385, Laboratory glassware BurettesISO 648, Laboratory glassware Single-volume pipettesISO 1042, Labora
21、tory glassware One-mark volumetric flasksISO 3696, Water for analytical laboratory use Specification and test methods .ISO 4787, Laboratory glassware Volumetric instruments Methods for testing of capacity and for useISO 9599, Copper, lead, zinc and nickel sulfide concentrates Determination of hygros
22、copic moisture content of the analysis sample Gravimetric method3 PrincipleDecomposition of the concentrate in hydrochloric and nitric acids. Dissolution of the digestion residue in hydrochloric acid and measurement by flame atomic absorption at 328,1 nm.4 ReagentsDuring the analysis, use only reage
23、nts of recognized analytical grade and water that complies with grade 2 of ISO 3696.4.1 Silver metal, minimum 99,99 % purity.4.2 Nitric acid, (201,42 g/ml), chloride content AC (12)If this condition exists, the difference between the reported result and the certified value is statistically significa
24、nt.wherecis the final result, in grams of silver per tonne, of the certified reference material;Acis the certified value, in grams of silver per tonne, of the certified reference material;C is a quantity, in grams of silver per tonne, depending on the type of the certified reference material used.Th
25、e reference materials used for this purpose should be prepared and certified in accordance with ISO Guide 35.6 ISO 2015 All rights reservedBS ISO 15247:2015ISO 15247:2015(E)Where the reference material is certified/characterized by an interlaboratory test programme, the quantity C, in grams of silve
26、r per tonne, is given by Formula (13):CssnsA=+22L2 r2c (13)wheres2Ac is the variance of the certified value;n is the number of replicate determinations.Where the reference material is certified/characterized by one laboratory, the quantity C, in grams of silver per tonne, is given by the following e
27、quation:Cssn=+22L2 r2(14)It is recommended that this type of certified reference material should be avoided, unless the particular CRM is known to have an unbiased certified value.10 Test reportsThe test report shall include the following information:a) identification of the sample;b) a reference to
28、 this International Standard, i.e. ISO 15247;c) mass fraction of cadmium in the sample, expressed as a percentage;d) date on which the test was carried out;e) any occurrences noticed during the determination which could have had an influence on the results. ISO 2015 All rights reserved 7BS ISO 15247
29、:2015ISO 15247:2015(E)Annex A (normative) Procedure for the preparation and determination of the mass of a predried test portionA.1 GeneralThis Annex sets out a method for the preparation and determination of the mass of a predried test portion in the analysis of zinc sulfide concentrates.The method
30、 is applicable to zinc sulfide concentrates not susceptible to oxidation and having hygroscopic moisture contents ranging from 0,05 % to 2 %.A.2 PrincipleThe test portion to be used for analysis is dried in air in an oven maintained at 105 C 5 C. The dried test portion is then weighed and used for t
31、he analysis. No correction for moisture is requiredA.3 ReagentA.3.1 Desiccant, such as self-indicating silica gel or anhydrous magnesium perchlorate.WARNING Care needs to be taken whenever disposing of exhausted magnesium perchlorate and all other laboratory chemicals. Environmental regulations ofte
32、n apply. Users should seek specialists advice to determine an appropriate, effective, health-conscious, safety-conscious, and environmentally sound means of disposal.A.4 ApparatusOrdinary laboratory equipment and the following.A.4.1 Analytical balance, sensitive to 0,1 mg.A.4.2 Weighing vessels, of
33、glass or silica or corrosion-resistant metal, with externally-fitting airtight covers. For small test portions (less than 3 g), the mass of the vessel shall be as small as possible, i.e. less than 20 g.A.4.3 Laboratory oven, capable of maintaining a temperature of 105 C 5 C.A.5 ProcedureA.5.1 Prepar
34、ation of the weighing vesselDry the weighing vessel and its cover (A.4.2) by heating in the laboratory oven (A.4.3) at 105 C 5 C for 1 h. Transfer the vessel and its cover to a desiccator containing a suitable fresh desiccant (A.3.1) and allow to cool to ambient temperature.8 ISO 2015 All rights res
35、ervedBS ISO 15247:2015ISO 15247:2015(E)A.5.2 Test portionTare the dried weighing vessel and vessel cover (A.5.1). Immediately add a proportion of the laboratory sample to provide a suitable pre-dried test portion. An accurate total mass of the test portion and weighing vessel is not required at this
36、 point.A.5.3 Determination of the test-portion dry massTransfer the uncovered weighing vessel and test portion and vessel cover to the laboratory oven (A.4.3) and dry at 105 C 5 C for 2 h. After the two-hour period, remove the weighing vessel and dry test portion from the oven, replace the vessel co
37、ver, and allow cooling to ambient temperature in the desiccator. When cool, remove the weighing vessel and dry test portion and vessel cover from the desiccator and weigh to the nearest 0,1 mg (m1) after slightly lifting the cover and quickly replacing it.Transfer the test portion into the appropria
38、te analytical apparatus and immediately re-weigh the empty weighing vessel and vessel cover. Record the mass (m2) to the nearest 0,1 mg.For new concentrates of unknown characteristics, it is advisable to repeat the drying for another 2 h at 105 C 5 C and to re-weigh the weighing vessel and test port
39、ion plus vessel cover to the nearest 0,1 mg (m1). The mass of the test portion can be considered to be constant if the difference between m1and m1is less than or equal to 0,5 mg. If this condition is not achieved, the drying and weighing steps should be repeated.A.6 Calculation of the dry mass of th
40、e test portionThe dry mass of the test portion m3, in grams, is given by Formula (A.1):m3= m1 m2(A.1)wherem1is the mass, in grams, of the dried test portion plus the weighing vessel and its cover;m2is the mass, in grams, of the empty weighing vessel plus its cover.The mass of the dry test portion is
41、 the mass to be used to calculate the element content in the laboratory sample on a dry basis. No correction for hygroscopic moisture is required. ISO 2015 All rights reserved 9BS ISO 15247:2015ISO 15247:2015(E)Annex B (normative) Flowsheet of the procedure for the acceptance of analytical values fo
42、r test samplesNOTE r is defined in 9.2.Figure B.1 Flowsheet of the procedure for the acceptance of analytical values for test samples10 ISO 2015 All rights reservedBS ISO 15247:2015ISO 15247:2015(E)Annex C (informative) Derivation of precision equationsC.1 GeneralThis International Standard was test
43、ed in an interlaboratory test programme involving eight countries and 15 laboratories. Five samples of zinc concentrate covering the range up to 60 % (m/m) were analysed to determine the silver content. The test programme was designed to determine the repeatability and within-laboratory and between
44、laboratories reproducibilities in general, using the principles of ISO 5725-2.C.2 Design of the test programmeThe analytical test programme was designed with the aim of providing maximum information. Each laboratory used two samples (two bags) of each concentrate and each sample was analysed twice i
45、ndependently.C.3 Test samplesThis test programme used five samples of zinc concentrate. The composition of these samples is shown in Table C.1.Table C.1 Composition of copper concentrated samplesElement UnitSample numbers89/1a89/2a89/3a91/16 93/1bCu % (m/m) 0,61 0,34 0,22 0,53 0,23Pb % (m/m) 3,5 3,0
46、1 5,54 3,72 3,24Zn % (m/m) 47,14 53,69 50,15 46,76 46,68Au g/t 10 3 0,5 7 2Ag g/t 300 130 340 19 15S % (m/m) 31,25 31,44 26,68 30,28 26,51Fe % (m/m) 8,83 5,09 5,18 10,51 6,7SiO2% (m/m) 3,42 4,35 7, 33 3,78 12,74Al2O3% (m/m) 0,73 0,31 0,46 0,42 1,2CaO % (m/m) 0,78 0,86 0,78 0,6 0,72K2O % (m/m) 0,32 0
47、,16 0,16 0,22 0,31MnO % (m/m) 0,55 0,64 0,3 0,14 0,15aCominco (Canada).bPeak (Australia).C.4 Statistical evaluationThe procedure for statistical evaluation is illustrated schematically in Figure C.1. The results of the statistical evaluation are summarized in Table C.2. ISO 2015 All rights reserved
48、11BS ISO 15247:2015ISO 15247:2015(E)Figure C.1 Flowsheet of procedure for statistical evaluation of analytical data resulting from international testsThe estimated precisions (sr, sL, r, and P) are plotted against their corresponding sample means on a graph as shown in Figure C.2 and the regression
49、equations of these precisions against sample means were computed and are presented in Table C.2.12 ISO 2015 All rights reservedBS ISO 15247:2015ISO 15247:2015(E)Table C.2 Summary of precisions for all samples SilverSample number(see Table C.1)kOk nOnXr P srsLsL/sr891 15 15 58 58 300,066 86,044 256,032 30,404 90,471 2,98892 15 15 57 57 131,741 50,124 168,962 17,712 59,704 3,37893 15 15 58 58 338,620 92,183 345,901 32,573 120,813 3,719116 15 15 58 55 18,877 0,769 7 46,0
