ISO 15661:2020
(Main)Copper and nickel sulfide ores and concentrates — Determination of total chlorine content — Alkaline fusion and potentiometric titration method
Copper and nickel sulfide ores and concentrates — Determination of total chlorine content — Alkaline fusion and potentiometric titration method
This document specifies an analytical method for the determination of total chlorine content using alkaline fusion and potentiometric titration. This method is applicable to copper and nickel sulfide ores and concentrates having chlorine content in the following ranges: a) Method 1: 80 µg/g to 4 300 µg/g b) Method 2: 70 µg/g to 4 300 µg/g
Minerais et concentrés de sulfure de cuivre et de sulfure de nickel — Détermination de la teneur totale en chlore — Méthode par fusion alcaline et par titrage potentiométrique
General Information
Standards Content (Sample)
INTERNATIONAL ISO
STANDARD 15661
First edition
2020-09
Copper and nickel sulfide ores and
concentrates — Determination of total
chlorine content — Alkaline fusion
and potentiometric titration method
Minerais et concentrés de sulfure de cuivre et de sulfure de nickel —
Détermination de la teneur totale en chlore — Méthode par fusion
alcaline et par titrage potentiométrique
Reference number
©
ISO 2020
© ISO 2020
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: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii © ISO 2020 – All rights reserved
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 2
5 Reagents . 2
6 Apparatus . 4
7 Instrument operating parameters . 4
8 Sample . 4
8.1 Laboratory sample . 4
8.2 Test sample . 5
9 Procedure. 5
9.1 Number of blank testing . 5
9.2 Number of determinations . 5
9.3 Determination . 5
9.3.1 General. 5
9.3.2 Decomposition of the test portion by fusion with a mixture of carbonate salts . 5
9.3.3 Decomposition of the test portion by fusion with a mixture of potassium salts . 6
9.3.4 Oxidation of sulfide . 7
9.3.5 Preparation of solution for titration . 7
9.3.6 Potentiometric titration . 7
10 Expression of results . 8
11 Precision and accuracy . 9
11.1 Expression of precision . 9
11.2 Method for obtaining the final result .10
11.3 Precision between laboratories .10
11.4 Check of trueness .11
12 Test report .12
Annex A (informative) Procedure for the preparation and determination of the mass of a
predried test portion .13
Annex B (normative) Flow chart of the procedure for the acceptance of analytical values for
test samples .15
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 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 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 2020 – All rights reserved
INTERNATIONAL STANDARD ISO 15661:2020(E)
Copper and nickel sulfide ores and concentrates —
Determination of total chlorine content — Alkaline fusion
and potentiometric titration method
CAUTION — The use of this document can involve hazardous materials, operations and
equipment. This document does not purport to address all of the safety issues associated with
its use. It is the responsibility of the user of this document to establish appropriate safety and
health practices and determine the applicability of regulatory limitations prior to its use.
1 Scope
This document specifies an analytical method for the determination of total chlorine content using
alkaline fusion and potentiometric titration.
This method is applicable to copper and nickel sulfide ores and concentrates having chlorine content in
the following ranges:
a) Method 1: 80 µg/g to 4 300 µg/g
b) Method 2: 70 µg/g to 4 300 µg/g
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, Copper, lead, zinc and nickel concentrates — Sampling procedures for determination of metal
and moisture content
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 fusion with a mixture of sodium carbonate and potassium carbonate
or with a mixture of potassium nitrate and potassium hydroxide. The fusion mixture is dissolved in
water and the sulfide contained is oxidized with hydrogen peroxide.
At the acid pH, the chloride content is determined by potentiometric titration with silver nitrate solution
after a known addition of the analyte.
5 Reagents
During the analysis, use only reagents of recognized analytical reagent grade and water that conforms
with grade 2 of ISO 3696. Particular care should be taken to ensure all reagents are high purity.
5.1 Sodium carbonate (Na CO ), high purity.
2 3
5.2 Potassium carbonate (K CO ), high purity.
2 3
5.3 Potassium nitrate (KNO ), high purity.
5.4 Potassium hydroxide (KOH), high purity.
5.5 Sodium chloride (NaCl), high purity.
5.6 Sodium bromide (NaBr), high purity.
5.7 Silver nitrate (AgNO ), high purity.
5.8 Flux mixture.
Mix one portion of anhydrous sodium carbonate (5.1) and one portion of potassium carbonate (5.2).
If the grain size of some reagent is significantly different from the other, a size reduction and
homogenization could be necessary.
Preferably use anhydrous reagent.
5.9 Methyl orange (C H N NaO ), high purity.
14 14 3 3
5.10 Nitric acid (HNO ), ρ20 = 1,4 g/ml, AR grade.
5.11 Hydrogen peroxide (H O ), 30 % purity.
2 2
5.12 Nitric acid solution (HNO ), volume fraction 1:1.
To a 1 000 ml volumetric flask add approximately 400 ml of deionized water and then 500 ml of
concentrated nitric acid (5.10). Cool to room temperature, dilute to volume and homogenize.
5.13 Sodium chloride solution (NaCl), 0,01 mol/l.
Weigh 0,584 4 g of sodium chloride (5.5), oven-dried at 105 °C for approximately 1 h, and transfer
to a 50 ml beaker. Adjust the mass before weighing according to the purity of the reagent used
(mass = 0,584 4 × 100/purity). Transfer to a glass volumetric flask of 1 000 ml using deionized water.
Dissolve, dilute to volume with deionized water and homogenize.
2 © ISO 2020 – All rights reserved
5.14 Sodium bromide solution (NaBr), 0,01 mol/l.
Weigh 1,028 9 g of sodium bromide (5.6), oven-dried at 105°C for approximately 1 h, and transfer to a
50 ml beaker. Adjust the mass to weigh according to the purity of the reagent used (m = 1,028 9 × 100/
purity). Transfer to a glass volumetric flask of 1 000 ml using deionized water. Dissolve and dilute to
volume with deionized water and homogenize.
5.15 Methyl orange solution, 0,1 % mass fraction.
Dissolve 0,5 g of methyl orange (5.9) into a 500 ml flask with deionized water.
5.16 Deionized water.
5.17 Silver nitrate solution (AgNO ), 0,01 mol/l.
Dissolve 1,698 7 g of silver nitrate (5.7) in 1 l of deionized water. Stir to dissolve and allow to cool.
Standardize this solution as spe
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.