Rubber — Determination of metal content by atomic absorption spectrometry — Part 6: Determination of magnesium content

This document specifies an atomic absorption spectrometric method for the determination of the magnesium content of natural rubber latex concentrate, raw natural rubber and products made from natural rubber.

Caoutchouc — Dosage du métal par spectrométrie d'absorption atomique — Partie 6: Dosage du magnésium

General Information

Status
Published
Publication Date
24-Sep-2018
Current Stage
6060 - International Standard published
Due Date
23-Nov-2019
Completion Date
25-Sep-2018
Ref Project

Relations

Buy Standard

Standard
ISO 6101-6:2018 - Rubber -- Determination of metal content by atomic absorption spectrometry
English language
9 pages
sale 15% off
Preview
sale 15% off
Preview

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 6101-6
Second edition
2018-09
Rubber — Determination of metal
content by atomic absorption
spectrometry —
Part 6:
Determination of magnesium content
Caoutchouc — Dosage du métal par spectrométrie d'absorption
atomique —
Partie 6: Dosage du magnésium
Reference number
ISO 6101-6:2018(E)
ISO 2018
---------------------- Page: 1 ----------------------
ISO 6101-6:2018(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2018

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
Fax: +41 22 749 09 47
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii © ISO 2018 – All rights reserved
---------------------- Page: 2 ----------------------
ISO 6101-6:2018(E)
Contents Page

Foreword ........................................................................................................................................................................................................................................iv

1 Scope ................................................................................................................................................................................................................................. 1

2 Normative references ...................................................................................................................................................................................... 1

3 Terms and definitions ..................................................................................................................................................................................... 1

4 Principle ........................................................................................................................................................................................................................ 2

5 Reagents ........................................................................................................................................................................................................................ 2

6 Apparatus ..................................................................................................................................................................................................................... 2

7 Sampling ........................................................................................................................................................................................................................ 3

8 Procedure..................................................................................................................................................................................................................... 3

8.1 Preparation of test portion ........................................................................................................................................................... 3

8.2 Preparation of test solution ......................................................................................................................................................... 3

8.2.1 Ashing of test portion (destruction of organic matter) .................................................................. 3

8.2.2 Dissolution of inorganic residue ........................................................................................................................ 4

8.3 Preparation of calibration graph ............................................................................................................................................. 4

8.3.1 Preparation of standard solutions .................................................................................................................... 4

8.3.2 Spectrometric measurements .............................................................................................................................. 4

8.3.3 Plotting the calibration graph ............................................................................................................................... 4

8.4 Determination ......................................................................................................................................................................................... 5

8.4.1 Spectrometric measurements .............................................................................................................................. 5

8.4.2 Dilution..................................................................................................................................................................................... 5

8.4.3 Blank determination ..................................................................................................................................................... 5

8.4.4 Number of determinations...................................................................................................................................... 5

8.5 Expression of results .......................................................................................................................................................................... 5

9 Precision ....................................................................................................................................................................................................................... 6

10 Test report ................................................................................................................................................................................................................... 6

Annex A (Informative) Method of standard additions ....................................................................................................................... 7

Annex B (Informative) Precision .............................................................................................................................................................................. 8

Bibliography ................................................................................................................................................................................................................................ 9

© ISO 2018 – All rights reserved iii
---------------------- Page: 3 ----------------------
ISO 6101-6:2018(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 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 45, Rubber and rubber products,

Subcommittee SC 2, Testing and analysis.

This second edition cancels and replaces the first edition (ISO 6101-6:2011), which has been technically

revised.
The main changes compared to the previous edition are as follows:
— The procedure for the destruction of organic matter has been further detailed;

— Formula (2) in 8.5 has been changed to magnesium content expressed as milligram per kilogram;

— Precision data have been updated in Annex B.
A list of all parts in the ISO 6101 series can be found on the ISO website.

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 2018 – All rights reserved
---------------------- Page: 4 ----------------------
INTERNATIONAL STANDARD ISO 6101-6:2018(E)
Rubber — Determination of metal content by atomic
absorption spectrometry —
Part 6:
Determination of magnesium content

WARNING 1 — Persons using this document should be familiar with normal laboratory practice.

This document does not purport to address all of the safety problems, if any, associated with its

use. It is the responsibility of the user to establish appropriate safety and health practices and to

determine applicability of any national regulatory conditions.

WARNING 2 — Certain procedures specified in this document might involve the use or generation

of substances, or the generation of waste, that could constitute a local environmental hazard.

Reference should be made to appropriate documentation on safe handling and disposal after use.

1 Scope

This document specifies an atomic absorption spectrometric method for the determination of the

magnesium content of natural rubber latex concentrate, raw natural rubber and products made from

natural rubber.
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 123, Rubber latex — Sampling
ISO 124, Latex, rubber — Determination of total solids content
ISO 247-1, Rubber — Determination of ash — Part 1: Dry combustion technique
ISO 648, Laboratory glassware — Single-volume pipettes
ISO 835, Laboratory glassware — Graduated pipettes
ISO 1042, Laboratory glassware — One-mark volumetric flasks
ISO 1772, Laboratory crucibles in porcelain and silica

ISO 1795, Rubber, raw natural and raw synthetic — Sampling and further preparative procedures

3 Terms and definitions
No terms and definitions are listed in this document.

ISO and IEC maintain terminological database for use in standardization at the following address:

— ISO Online browsing platform: available at http: //www .iso .org/obp
— IEC Electropedia: available at http: //www .electropedia .org/
© ISO 2018 – All rights reserved 1
---------------------- Page: 5 ----------------------
ISO 6101-6:2018(E)
4 Principle

A test portion is ashed at 550 °C ± 25 °C for raw natural rubber or at 950 °C ± 25 °C for rubber products

having a high carbon black content in accordance with ISO 247-1. The ash is dissolved in dilute nitric acid.

The solution is aspirated into an atomic absorption spectrometer and the absorption is measured at a

wavelength of 285,2 nm, using a magnesium hollow-cathode lamp as the magnesium emission source.

5 Reagents

During the analysis, unless otherwise stated, use only reagents of recognized analytical grade and only

distilled water or water of equivalent purity.
5.1 Concentrated nitric acid, ρ = 1,41 g/cm , 65 % (m/m) to 70 % (m/m).

5.2 Dilute nitric acid, 1,6 % (by mass), carefully pipette 11,5 cm of concentrated nitric acid (5.1) into

a 1 000 cm one-mark volumetric flask, making up to the mark with water, and mix thoroughly.

5.3 Standard magnesium stock solution, containing 1 g of Mg per cubic decimetre.

Either use a commercially available standard magnesium solution or prepare as follows:

Grind metallic magnesium, purity greater than 99 % (by mass). Weigh 1 g to the nearest 0,1 mg in a

3 3 3

250 cm conical flask (6.13) and dissolve it in a mixture of 100 cm of dilute nitric acid (5.2) and 10 cm

of concentrated nitric acid (5.1). Transfer it to a 1 000 cm one-mark volumetric flask (6.4), dilute to the

mark with dilute nitric acid (5.2) and mix thoroughly.
1 cm of this standard solution contains 1 000 μg of Mg.

5.4 Standard magnesium solution, containing 10 µg of Mg per cubic centimetre, carefully pipette

3 3

10 cm of standard magnesium stock solution (5.3) into a 1 000 cm one-mark volumetric flask, making

up to the mark with dilute nitric acid (5.2), and mix thoroughly. Prepare this solution preferably on the

day of use.
6 Apparatus

6.1 Atomic absorption spectrometer, fitted with a burner fed with acetylene and compressed air

and also fitted with a magnesium hollow-cathode lamp capable of emitting radiation of the require

...

Questions, Comments and Discussion

Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.