ISO 10101-1:2022
(Main)Natural gas — Determination of water by the Karl Fischer method — Part 1: General requirements
Natural gas — Determination of water by the Karl Fischer method — Part 1: General requirements
This document specifies general requirements for the determination of water in natural gas using the Karl Fischer method (see Reference [1]). ISO 10101-2 and ISO 10101-3 specify two individual methods of determination, a titration procedure and a coulometric procedure, respectively.
Gaz naturel — Dosage de l'eau par la méthode de Karl Fischer — Partie 1: Exigences générales
General Information
Relations
Standards Content (Sample)
INTERNATIONAL ISO
STANDARD 10101-1
Second edition
2022-08
Natural gas — Determination of water
by the Karl Fischer method —
Part 1:
General requirements
Gaz naturel — Dosage de l'eau par la méthode de Karl Fischer —
Partie 1: Exigences générales
Reference number
ISO 10101-1:2022(E)
© ISO 2022
---------------------- Page: 1 ----------------------
ISO 10101-1:2022(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2022
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 2022 – All rights reserved
---------------------- Page: 2 ----------------------
ISO 10101-1:2022(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 1
4.1 General . 1
4.2 Principle of the titration method . 1
4.3 Principle of the coulometric method . 2
5 Reactions and interferences .2
6 Sampling . 3
7 Measurement uncertainty .3
Bibliography . 4
iii
© ISO 2022 – All rights reserved
---------------------- Page: 3 ----------------------
ISO 10101-1:2022(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 on 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 the following
URL: www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 193, Natural Gas, Subcommittee SC 1,
Analysis of natural gas, in collaboration with the European Committee for Standardization (CEN)
Technical Committee CEN/TC 238, Test gases, test pressures, appliance categories and gas appliance types,
in accordance with the Agreement on technical cooperation between ISO and CEN (Vienna Agreement).
This second edition cancels and replaces the first edition (ISO 10101-1:1993), which has been technically
revised.
The main changes are as follows:
— Clause 2 and Bibliography were revised;
— New fixed structure numbering inserted.
A list of all parts in the ISO 10101 series can be found on the ISO website.
iv
© ISO 2022 – All rights reserved
---------------------- Page: 4 ----------------------
ISO 10101-1:2022(E)
Introduction
Water vapour may be present in natural gas due to, for example, natural occurrence in the well
production stream, the storage of gas in underground reservoirs, transmission or distribution through
mains containing moisture or other reasons.
The Karl Fischer method for the determination of moisture has several practical advantages compared
to other methods for moisture determination, such as accuracy, speed and selectivity.
The Karl Fischer method is selective for water, because the titration reaction itself consumes water.
The Karl Fischer (KF) titration can be divided into two basic techniques depending on the application
range – volumetric and coulometric KF titration. The two analysis techniques differ in the mode of
iodine addition or generation.
KF titration is essentially based on the Bunsen reaction used for the determination of sulphur dioxide
in aqueous solution:
22HO++SO IH→+SO HI
22 22 4
If an excess of sulphur dioxide with simultaneous neutralization of the sulphuric acid formed shift the
reaction equilibrium to the right, the Bunsen reaction can also be used for the determination of water.
Karl Fischer used pyridine as (neutralization) base, thus developing the classical KF reagent. This was
[9]
a solution of iodine and sulphur dioxide in a solvent mixture of pyridine and methanol . The fact that
the pyridine contained in the reagent has a strong unpleasant odour and toxicity and the reaction
[9]
runs stoichiometrically only within a certain pH range led to the revision of the KF reagents . Scholz
formulated the following KF reaction based on imidazole:
CH OH+SO+RN→[]RNHSOCH
32 33
where RN = Base.
HO+I +R[]NH SO CH +2RN→[]RNHSOCH+2R[]NH I
22 33 43
Volumetric KF titration is preferably used for the determination of large amounts of water in the range
[10]
of 1 mg to 100 mg
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.