EN 15491:2025

Ethanol as a blending component for petrol - Determination of total acidity - Colour indicator titration method

This document specifies a method for determining the total acidity, calculated as acetic acid, of ethanol to be used in petrol blends. It is applicable to ethanol having total acid contents of between 0,003 % (m/m) and 0,015 % (m/m).
NOTE   For the purposes of this document, the terms "% (m/m)" and "% (V/V)" are used to represent the mass fraction and the volume fraction, respectively.
WARNING - Use of this document can involve hazardous materials, operations and equipment. This document does not purport to address all of the safety problems associated with its use. It is the responsibility of the user of this document to take appropriate measures to ensure the safety and health of personnel prior to the application of the document, and to fulfil statutory and regulatory restrictions for this purpose.

Ethanol zur Verwendung als Blendkomponente in Ottokraftstoff - Bestimmung der Gesamtsäurezahl - Farbindikator-Titration

Dieses Dokument legt ein Prüfverfahren zur Bestimmung der Gesamtsäurezahl, angegeben als Essigsäure, von Ethanol in der Anwendung als Blendkomponente in Ottokraftstoff fest. Das Prüfverfahren ist anwendbar für Ethanol mit Gesamtsäurezahlen im Bereich von 0,003 % (m/m) bis 0,015 % (m/m).
ANMERKUNG   Für die Zwecke dieses Dokuments wird zur Angabe des Massenanteils einer Substanz der Ausdruck „% (m/m)“ und für den Volumenanteil einer Substanz der Ausdruck „% (V/V)“ verwendet.
WARNUNG — Die Anwendung dieses Dokuments kann die Anwendung gefährlicher Stoffe, Arbeitsgänge und Geräte mit sich bringen. Dieses Dokument beansprucht nicht, alle damit verbundenen Sicherheitsprobleme zu behandeln. Es liegt in der Verantwortung der Person, die das Dokument anwendet, vor der Anwendung geeignete Maßnahmen für die Sicherheit und den Gesundheitsschutz des Personals zu ergreifen, und dafür Sorge zu tragen, dass behördliche und gesetzliche Maßnahmen eingehalten werden.

Ethanol comme base de mélange à l'essence - Détermination de l'acidité totale - Méthode de titrage par indicateur coloré

Le présent document spécifie une méthode pour la détermination de l’acidité totale, exprimée en équivalent d’acide acétique, dans l’éthanol utilisé comme constituant d’essence pour automobiles. Elle s’applique aux échantillons d’éthanol ayant une acidité totale comprise entre 0,003 % (m/m) et 0,015 % (m/m).
NOTE   Pour les besoins du présent document, les termes “% (m/m)” et “% (V/V)” sont utilisés pour représenter la fraction massique et la fraction volumique, respectivement.
AVERTISSEMENT — L'utilisation du présent document peut impliquer l'intervention de produits, d'opérations et d'équipements à caractère dangereux. Ce document n'a pas la prétention d’aborder tous les problèmes de sécurité concernés par son usage. Il est de la responsabilité de l'utilisateur de ce document de prendre les mesures appropriées pour assurer la sécurité et préserver la santé du personnel avant l’application du document et de déterminer l'applicabilité de restrictions réglementaires ou toute autre à cette fin.

Etanol kot komponenta za dodajanje motornemu bencinu - Določanje celotne kislosti - Titracijska metoda z barvnim indikatorjem

General Information

• Status: Published
• Publication Date: 04-Mar-2025
• ICS: 75.160.20 - Liquid fuels
• Technical Committee: CEN/TC 19 - Petroleum products, lubricants and related products
• Drafting Committee: CEN/TC 19 - Petroleum products, lubricants and related products
• Current Stage: 6060 - Definitive text made available (DAV) - Publishing
• Start Date: 05-Mar-2025
• Due Date: 02-Apr-2026
• Completion Date: 05-Mar-2025
• Directive: 98/70/EC - Quality of petrol and diesel fuels (Dir. 93/12/EEC amendment)
• Mandate: M/344 - Mandate to CEN on Ethanol as an oxygen extender to gasoline
• Ref Project: SIST EN 15491:2025 - Ethanol as a blending component for petrol - Determination of total acidity - Colour indicator titration method

Relations

• Replaces: EN 15491:2021 - Ethanol as a blending component for petrol - Determination of total acidity - Colour indicator titration method
• Effective Date: 27-Dec-2023

Standards Content (Sample)

SLOVENSKI STANDARD
01-maj-2025
Nadomešča:
SIST EN 15491:2022
Etanol kot komponenta za dodajanje motornemu bencinu - Določanje celotne
kislosti - Titracijska metoda z barvnim indikatorjem
Ethanol as a blending component for petrol - Determination of total acidity - Colour
indicator titration method
Ethanol zur Verwendung als Blendkomponente in Ottokraftstoff - Bestimmung der
Gesamtsäurezahl - Farbindikator-Titration
Ethanol comme base de mélange à l'essence - Détermination de l'acidité totale -
Méthode de titrage par indicateur coloré
Ta slovenski standard je istoveten z: EN 15491:2025
ICS:
71.080.60 Alkoholi. Etri Alcohols. Ethers
75.160.20 Tekoča goriva Liquid fuels
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN 15491
EUROPEAN STANDARD
NORME EUROPÉENNE
March 2025
EUROPÄISCHE NORM
ICS 75.160.20 Supersedes EN 15491:2021
English Version
Ethanol as a blending component for petrol -
Determination of total acidity - Colour indicator titration
method
Ethanol comme base de mélange à l'essence - Ethanol zur Verwendung als Blendkomponente in
Détermination de l'acidité totale - Méthode de titrage Ottokraftstoff - Bestimmung der Gesamtsäurezahl -
par indicateur coloré Farbindikator-Titration
This European Standard was approved by CEN on 15 January 2025.

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 CEN-CENELEC 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 CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2025 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 15491:2025 E
worldwide for CEN national Members.

Contents Page
European foreword . 3
1 Scope . 4
2 Normative references . 4
3 Terms and definitions . 4
4 Principle . 4
5 Reagents and materials . 5
6 Apparatus . 6
7 Sampling and sample handling . 6
8 Procedure. 6
9 Calculation . 7
10 Expression of results . 7
11 Precision . 7
11.1 General . 7
11.2 Repeatability, r . 7
11.3 Reproducibility, R . 7
12 Test report . 8
Bibliography . 9

European foreword
This document (EN 15491:2025) has been prepared by Technical Committee CEN/TC 19 “Gaseous and
liquid fuels, lubricants and related products of petroleum, synthetic and biological origin”, 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 September 2025, and conflicting national standards
shall be withdrawn at the latest by September 2025.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN 15491:2021.
In comparison with the previous edition EN 15491:2021, the following technical modification has been
made:
— sparging with nitrogen before titration has been added to 8.4 and sparging during the titration has
been made mandatory for clarification to the user and for better comparison of the results. This has
no effect on the method precision.
This document has been prepared under a standardization request addressed to CEN by the European
Commission. The Standing Committee of the EFTA States subsequently approves these requests for its
Member States.
Any feedback and questions on this document should be directed to the users’ national standards body.
A complete listing of these bodies can be found on the CEN website.
According to the CEN-CENELEC Internal Regulations, the national standards organisations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and the
United Kingdom.
1 Scope
This document specifies a method for determining the total acidity, calculated as acetic acid, of ethanol
to be used in petrol blends. It is applicable to ethanol having total acid contents of between
0,003 % (m/m) and 0,015 % (m/m).
NOTE For the purposes of this document, the terms “% (m/m)” and “% (V/V)” are used to represent the mass
fraction and the volume fraction, respectively.
WARNING — Use of this document can involve hazardous materials, operations and equipment.
This document does not purport to address all of the safety problems associated with its use. It
is the responsibility of the user of this document to take appropriate measures to ensure the
safety and health of personnel prior to the application of the document, and to fulfil statutory
and regulatory restrictions for this purpose.
2 Normative references
The foll
...