ISO 13546:2021

FINAL
INTERNATIONAL ISO/FDIS
DRAFT
STANDARD 13546
ISO/TC 183
Copper concentrates —
Secretariat: SA
Determination of mercury content
Voting begins on:
2021­04­26 — Cold vapour atomic absorption
spectrometric method
Voting terminates on:
2021­06­21
RECIPIENTS OF THIS DRAFT ARE INVITED TO
SUBMIT, WITH THEIR COMMENTS, NOTIFICATION
OF ANY RELEVANT PATENT RIGHTS OF WHICH
THEY ARE AWARE AND TO PROVIDE SUPPOR TING
DOCUMENTATION.
IN ADDITION TO THEIR EVALUATION AS
Reference number
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO­
ISO/FDIS 13546:2021(E)
LOGICAL, COMMERCIAL AND USER PURPOSES,
DRAFT INTERNATIONAL STANDARDS MAY ON
OCCASION HAVE TO BE CONSIDERED IN THE
LIGHT OF THEIR POTENTIAL TO BECOME STAN­
DARDS TO WHICH REFERENCE MAY BE MADE IN
©
NATIONAL REGULATIONS. ISO 2021

---------------------- Page: 1 ----------------------
ISO/FDIS 13546:2021(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO 2021
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
CH­1214 Vernier, Geneva
Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii © ISO 2021 – All rights reserved

---------------------- Page: 2 ----------------------
ISO/FDIS 13546:2021(E)

Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 1
5 Reagents . 2
6 Apparatus . 3
7 Sampling and sampling preparation . 4
7.1 Test sample . 4
7.2 Test portion . 4
8 Procedure. 4
8.1 Number of determinations . 4
8.2 Blank test . 4
8.3 Dissolution of the test portion . 4
8.4 Storage of digested solutions . 5
8.5 Preparation of sample solutions . 5
8.6 Preparation of test solutions . 5
8.7 Preparation of calibration solutions . 5
8.8 Preparation of mercury calibration graph . 5
8.9 Determination of mercury content in test solutions . 6
9 Expression of results . 6
10 Procedure for obtaining the final result . 6
11 Precision . 6
11.1 Expression of precision . 6
11.2 Procedure for obtaining the final result . 7
11.3 Precision between laboratories . 7
11.4 Check of trueness . 8
11.4.1 General. 8
11.4.2 Type of certified reference material or reference material. 8
11.4.3 Reference material certified or characterized by an interlaboratory test
programme . 8
11.4.4 Reference material certified or characterized by one laboratory . 9
12 Test report . 9
Annex A (normative) Procedure for obtaining the final results .10
Bibliography .11
© ISO 2021 – All rights reserved iii

---------------------- Page: 3 ----------------------
ISO/FDIS 13546:2021(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 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 non­governmental, 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 intended 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 .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 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 information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www .iso .org/
iso/ foreword .html.
This document was prepared by Technical Committee ISO/TC 183, Copper, lead, zinc and nickel ores and
concentrates.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www .iso .org/ members .html.
iv © ISO 2021 – All rights reserved

---------------------- Page: 4 ----------------------
FINAL DRAFT INTERNATIONAL STANDARD ISO/FDIS 13546:2021(E)
Copper concentrates — Determination of mercury content
— Cold vapour atomic absorption spectrometric method
WARNING — The use of this document can involve hazardous materials, operations and
equipment. It is the responsibility of the user of this document to establish appropriate health
and safety practices and determine the applicability of regulatory limitations prior to use.
1 Scope
This document specifies an acid digestion and vapour generation atomic absorption spectrometric
method for the determination of the mercury content in copper sulfide concentrate.
This document is applicable to mass fraction of mercury between 5 µg/g and 65 µg/g in copper sulfide
concentrates.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. 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 — Burettes
ISO 648, Laboratory glassware — Single-volume pipettes
ISO 1042, Laboratory glassware — One-mark volumetric flasks
ISO 3696, Water for analytical laboratory use — Specification and test methods
ISO 4787, Laboratory glassware — Volumetric instruments — Methods for testing of capacity and for use
ISO 9599, Copper, lead, zinc and nickel sulfide concentrates — Determination of hygroscopic moisture
content of the analysis sample — Gravimetric method
ISO 12743:2018, Copper, lead, zinc and nickel concentrates — Sampling procedures for determination of
metal and moisture content
ISO Guide 35, Reference materials — Guidance for characterization and assessment of homogeneity and
stability
3 Terms and definitions
No terms and definitions are listed in this document.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
4 Principle
The test portion is decomposed by treatment with hydrochloric and nitric acid at a temperature
of between 60 °C and 80 °C followed by the addition of potassium permanganate as oxidizing agent.
Subsequently, the potassium permanganate is reduced by hydroxylamine hydrochloride. The mercury
© ISO 2021 – All rights reserved 1

---------------------- Page: 5 ----------------------
ISO/FDIS 13546:2021(E)

vapour is generated by vapour generation using tin (II) chloride as reduction agent. The equipment is set
to measure the absorbance at 253,7 nm. The absorbances of the test and calibration solutions, including
those of certified or other reference materials, are compared to determine the mercury content.
5 Reagents
During the analysis, use only reagents of recognized analytical grade and grade 2 water in accordance
with ISO3696.
Reagents shall be selected or purified for the lowest possible blank value.
5.1 Tin (II) chloride dehydrate, (SnCl .2H O), containing < 5 mg/g mercury.
2 2
5.2 Potassium permanganate (KMnO ).
4
5.3 Hydroxylamine hydrochloride (HONH .HCl).
2
5.4 Mercury (II) chloride (HgCl ).
2
5.5 Nitric acid, ρ = 1,42 g/ml.
5.6 Hydrochloric acid, ρ = 1,16 g/ml to 1,19 g/ml.
5.7 Sulfuric acid, ρ = 1,84 g/ml.
5.8 Sulfuric acid solution, diluted 1 + 5.
5.9 Sulfuric acid solution, diluted 1+.
5.10 Aqua regia. Mix 300 ml of hydrochloric acid (5.6) and 100 ml nitric acid (5.5). Prepare freshly for
each batch of mercury determination.
5.11 Tin (II) chloride solution, 100 g/l. Add 10 g of tin (II) chloride (5.1) to 80 ml sulfuric acid solution
(5.9). Heat and swirl to dissolve. Cool the solution and dilute with deionized water to 100 ml and mix
thoroughly.
Continuously stir the solution with a magnetic stirrer for at least 2 h before use and maintain stirring
during analysis. Prepare weekly.
Hydrochloric acid may be used instead of sulfuric acid.
Alternative procedure:
Tin (II) chloride solution, 100 g/l: add 10 g of tin (II) chloride (5.1) to 20 ml of deionized water. Add
continuously 60 ml of sulfuric acid solution (5.8). Heat and swirl to dissolve. Cool, dilute to 100 ml with
deionized water and mix thoroughly.
5.12 Potassium permanganate
...