EN ISO 12937:2000

Petroleum products - Determination of water - Coulometric Karl Fischer titration method (ISO 12937:2000)

This International Standard specifies a method for the direct determination of water in petroleum products boiling
below 390 °C. It covers the mass fraction range 0,003 % (m/m) to 0,100%(m/m). It is not applicable to products
containing ketones or to residual fuel oils.
This International Standard may be applicable to lubricating base oils. However, the precision has not been
established for these materials.
The precision given in clause 12 is based upon data obtained using dual-cell, dual-electrolyte systems.
NOTE 1 A number of substances and classes of compounds associated with condensation or oxidation-reduction reactions
interfere in the determination of water by Karl Fischer titration. In petroleum products, the most common interferences are
hydrogen sulfide and mercaptan sulfur, however, mass fractions of these below 0,003 % (m/m) as sulfur will not cause
significant interference over the range 0,003 % (m/m) to 0,100%(m/m) water. Other organic sulfur compounds commonly
present such as sulfides, disulphides and thiophenes, do not interfere.
NOTE 2 An alternative procedure is provided for information in annex B for the direct determination of water over the range
0,003 % (V/V) to 0,100 % (V/V) in petroleum products. The limitations under which this alternative volume measurement may be
used are listed in annex B.
NOTE 3 For the purposes of this International Standard, the terms "% (m/m)" and "% (V/V)" are used to represent the mass
and volume fraction of a material respectively.

Mineralölerzeugnisse - Bestimmung des Wassergehaltes - Coulometrische Titration nach Karl Fischer (ISO 12937:2000)

Die Internationale Norm legt ein Verfahren zur direkten Bestimmung des Wassergehaltes durch coulometrische Titration nach Karl Fischer im Bereich von 0,003 % (m/m) bis 0,100 % (m/m) in Mineralölerzeugnissen mit Siedepunkt unterhalb von 390 °C. Die Bestimmung ist nicht anwendbar auf Produkte, die Ketone enthalten und auch nicht auf Rückstandsöle anwendbar.
Diese Internationale Norm kann für Schmieröle eingesetzt werden. Die Präzisionsdaten wurden jeodch nicht für diese Materialien ermittelt. Die Präzisionsdaten in Abschnitt 12 basieren auf Daten, die mit Dual-Zellen und Dual-Elektrolyten-Systemen ermittelt wurden.
ANMERKUNG 1   Bei der Bestimmung des Wassergehaltes durch Titration nach Karl Fischer stören eine Anzahl von Substanzen und Stoffklassen, die kondensieren können oder an Oxidations-Reduktions-Reaktionen teilnehmen können. Bei Mineralölerzeugnissen sind die am häufigsten störenden Substanzen Schwefelwasserstoff und Mercaptanschwefel; wenn deren Konzentration jedoch unter 0,003 % (m/m) liegt, wird die Störung bei einem Wassergehalt zwischen 0,003 % (m/m) und 0,100 % (m/m) unerheblich sein. Andere, üblicherweise anwesende organische Schwefelverbindungen, wie Sulfide, Disulfide und Thiophene, stören nicht.
ANMERKUNG 2   Ein alternatives Verfahren zur direkten Bestimmung des Wassergehaltes zwischen 0,003 % (V/V) und 0,100 % (V/V) in Mineralölerzeugnissen wird in Anhang B dargestellt. Die Einschränkungen, die für diese alternative Volumenmessung gelten, sind in Anhang B aufgezählt.
ANMERKUNG   3 - Für den Zweck dieser Internationalen Norm werden "% (m/m)" und "%(V/V)" für Massenanteile in % und Volumenanteile in % benutzt.

Produits pétroliers - Dosage de l'eau - Méthode de titrage Karl Fischer par coulométrie (ISO 12937:2000)

La présente Norme internationale prescrit une méthode de dosage direct de l'eau dans les produits pétroliers dont
le point d'ébullition est inférieur à 390 °C. Elle couvre la gamme des fractions massiques allant de 0,003 % (m/m) à
0,100 % (m/m). Elle ne s'applique pas aux essences contenant des cétones ni aux fuel-oils résiduels.
La présente Norme internationale peut être applicable aux huiles de base lubrifiantes. Cependant, la fidélité n'a
pas été établie pour ces produits.
La fidélité donnée à l'article 12 est basée sur des données obtenues avec une cellule double et un jeu de deux
solutions d'électrolytes.
NOTE 1 Lorsqu'elles sont associées à des réactions de condensation ou d'oxydoréduction, un certain nombre de
substances et de catégories de composés peuvent interférer pendant le dosage de l'eau par la méthode Karl Fischer. Dans le
cas des produits pétroliers, les interférences les plus courantes sont celles de l'hydrogène sulfuré et du soufre sous forme de
mercaptans. Cependant, si ces derniers se trouvent à des fractions massiques de soufre inférieures à 0,003 % (m/m), ils ne
provoquent pas d'interférences significatives entre 0,003 % (m/m) et 0,100 % (m/m) de teneur en eau. Les autres composés
soufrés organiques que l'on trouve couramment, tels que les sulfures, les disulfures et les thiophènes, n'interfèrent pas.
NOTE 2 L'annexe B donne à titre d'information un autre mode opératoire pour le dosage direct de l'eau dans les produits
pétroliers dans la gamme de 0,003 % (V/V) à 0,100 % (V/V). Les limites d'utilisation de cette méthode alternative de mesure du
volume sont décrites dans l'annexe B.
NOTE 3 Pour les besoins de la présente Norme internationale, les termes «% (m/m)» et «% (V/V)» sont utilisés pour
représenter respectivement les fractions massiques et les fractions volumiques d'un produit.

Naftni proizvodi - Določevanje vode - Metoda s kulometrično titracijo po Karlu Fischerju (ISO 12937:2000)

General Information

• Status: Published
• Publication Date: 31-Oct-2000
• ICS: 75.080 - Petroleum products in general
• Technical Committee: CEN/TC 19 - Petroleum products, lubricants and related products
• Drafting Committee: CEN/TC 19 - Petroleum products, lubricants and related products
• Current Stage: 9093 - Decision to confirm - Review Enquiry
• Start Date: 17-Dec-2010
• Completion Date: 17-Dec-2010
• Ref Project: SIST EN ISO 12937:2001 - Petroleum products - Determination of water - Coulometric Karl Fischer titration method (ISO 12937:2000)

Standards Content (Sample)

SLOVENSKI STANDARD
01-maj-2001
1DIWQLSURL]YRGL'RORþHYDQMHYRGH0HWRGDVNXORPHWULþQRWLWUDFLMRSR.DUOX
)LVFKHUMX,62
Petroleum products - Determination of water - Coulometric Karl Fischer titration method
(ISO 12937:2000)
Mineralölerzeugnisse - Bestimmung des Wassergehaltes - Coulometrische Titration nach
Karl Fischer (ISO 12937:2000)
Produits pétroliers - Dosage de l'eau - Méthode de titrage Karl Fischer par coulométrie
(ISO 12937:2000)
Ta slovenski standard je istoveten z: EN ISO 12937:2000
ICS:
75.080 Naftni proizvodi na splošno Petroleum products in
general
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN ISO 12937
NORME EUROPÉENNE
EUROPÄISCHE NORM
November 2000
ICS 75.080
English version
Petroleum products - Determination of water - Coulometric Karl
Fischer titration method (ISO 12937:2000)
Produits pétroliers - Dosage de l'eau - Méthode de titrage Mineralölerzeugnisse - Bestimmung des Wassergehaltes -
Karl Fischer par coulométrie (ISO 12937:2000) Coulometrische Titration nach Karl Fischer (ISO
12937:2000)
This European Standard was approved by CEN on 27 October 2000.
CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European
Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national
standards may be obtained on application to the Management Centre or to any CEN member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CEN member into its own language and notified to the Management Centre has the same status as the official
versions.
CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece,
Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36  B-1050 Brussels
© 2000 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 12937:2000 E
worldwide for CEN national Members.

Page 2
Foreword
The text of the International Standard ISO 12937:2000 has been prepared by Technical
Committee ISO/TC 28 "Petroleum products and lubricants" in collaboration with Technical
Committee CEN/TC 19 "Petroleum products, lubricants and related products", the secretariat
of which is held by NEN.
This European Standard shall be given the status of a national standard, either by publication
of an identical text or by endorsement, at the latest by May 2001, and conflicting national
standards shall be withdrawn at the latest by May 2001.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of
the following countries are bound to implement this European Standard: Austria, Belgium,
Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy,
Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United
Kingdom.
Endorsement notice
The text of the International Standard ISO 12937:2000 was approved by CEN as a European
Standard without any modification.

Page 3
Annex ZA (normative)
Normative references to international publications with their relevant European
publications
This European Standard incorporates by dated or undated reference, provisions from other
publications. These normative references are cited at the appropriate places in the text and the
publications are listed hereafter. For dated references, subsequent amendments to or revisions of
any of these publications apply to this European Standard only when incorporated in it by
amendment or revision. For undated references the latest edition of the publication referred to
applies (including amendments).
NOTE Where an International Publication has been modified by common modifications,
indicated by (mod.), the relevant EN/HD applies.
Publication Year Title EN Year
ISO 3170 1988 Petroleum liquids - Manual sampling EN ISO 3170 1998
ISO 3171 1988 Petroleum liquids - Automatic pipeline EN ISO 3171 1999
sampling
ISO 3696 1987 Water for analytical laboratory use - EN ISO 3696 1995
Specification and test methods

INTERNATIONAL ISO
STANDARD 12937
First edition
2000-11-01
Petroleum products — Determination of
water — Coulometric Karl Fischer titration
method
Produits pétroliers — Dosage de l'eau — Méthode de titrage Karl Fischer
par coulométrie
Reference number
ISO 12937:2000(E)
©
ISO 2000
ISO 12937:2000(E)
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ii © ISO 2000 – All rights reserved

ISO 12937:2000(E)
Contents Page
Foreword.iv
1 Scope .1
2 Normative references .1
3 Principle.2
4 Chemicals and materials.2
5 Apparatus .3
6 Sampling and sample preparation (see annex A) .3
7 Apparatus preparation .4
8 Apparatus check test .4
9 Procedure .5
10 Calculation.5
11 Expression of results .5
12 Precision.6
13 Test report .6
Annex A (normative) Sample handling .7
Annex B (informative) Alternative test method using volumetric determination of sample size .10
ISO 12937:2000(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.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 3.
Draft International Standards adopted by the technical committees are circulated to the member bodies for voting.
Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this International Standard may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights.
International Standard ISO 12937 was prepared by Technical Committee ISO/TC 28, Petroleum products and
lubricants, Subcommittee SC 6, Bulk cargo transfer, accountability, inspection and reconciliation.
Annex A forms a normative part of this International Standard. Annex B is for information only.
iv © ISO 2000 – All rights reserved

INTERNATIONAL STANDARD ISO 12937:2000(E)
Petroleum products — Determination of water — Coulometric Karl
Fischer titration method
WARNING — The use of this International Standard may involve hazardous materials, operations and
equipment. This International Standard does not purport to address all of the safety problems associated
with its use. It is the responsibility of the user of this International Standard to establish appropriate safety
and health practices and determine the applicability of regulatory limitations prior to use.
1 Scope
This International Standard specifies a method for the direct determination of water in petroleum products boiling
below 390 °C. It covers the mass fraction range 0,003 % (m/m)to 0,100%(m/m). It is not applicable to products
containing ketones or to residual fuel oils.
This International Standard may be applicable to lubricating base oils. However, the precision has not been
established for these materials.
The precision given in clause 12 is based upon data obtained using dual-cell, dual-electrolyte systems.
NOTE 1 A number of substances and classes of compounds associated with condensation or oxidation-reduction reactions
interfere in the determination of water by Karl Fischer titration. In petroleum products, the most common interferences are
hydrogen sulfide and mercaptan sulfur, however, mass fractions of these below 0,003 % (m/m) as sulfur will not cause
significant interference over the range 0,003 % (m/m)to 0,100%(m/m) water. Other organic sulfur compounds commonly
present such as sulfides, disulphides and thiophenes, do not interfere.
NOTE 2 An alternative procedure is provided for information in annex B for the direct determination of water over the range
0,003 % (V/V) to 0,100 % (V/V) in petroleum products. The limitations under which this alternative volume measurement may be
used are listed in annex B.
NOTE 3 For the purposes of this International Standard, the terms "% (m/m)" and "% (V/V)" are used to represent the mass
and volume fraction of a material respectively.
2 Normative references
The following normative documents contain provisions which, through reference in this text, constitute provisions of
this International Standard. For dated references, subsequent amendments to, or revisions of, any of these
publications do not apply. However, parties to agreements based on this International Standard are encouraged to
investigate the possibility of applying the most recent editions of the normative documents indicated below. For
undated references, the latest edition of the normative document referred to applies. Members of ISO and IEC
maintain registers of currently valid International Standards.
ISO 3170:1988, Petroleum liquids — Manual sampling.
ISO 3171:1988, Petroleum liquids — Automatic pipeline sampling.
ISO 3696:1987, Water for analytical laboratory use — Specification and test methods.
ISO 12937:2000(E)
3Principle
A sample is visually inspected (see 6.2.1). If clear and bright, and free from both water droplets and particulate
matter on swirling, a weighed portion is injected into the titration vessel of a coulometric Karl Fischer apparatus in
which iodine for the Karl Fischer reaction is generated coulometrically at the anode. When all the water has been
titrated, excess iodine is detected by an electrometric end-point detector and the titration is terminated. Based on
the stoichiometry of the reaction, one mole of iodine reacts with one mole of water, thus the quantity of water is
proportional to the total integrated current according to Faraday's Law.
If the sample is not clear and bright, or water droplets or p
...