SIST EN 12634:1999

Petroleum products and lubricants - Determination of acid number - Non-aqueous potentiometric titration method

This European Standard specifies a method for determination of acid number by potentiometric titration, of lubricating oils and additives soluble in mixtures of propan-2-ol, dimethylsulfoxide and toluene. It is applicable in the range 0,1 mg KOH/g to 250 mg KOH/g, and to unused and used lubricating oils and additives.

Mineralölerzeugnisse und Schmierstoffe - Bestimmung der Säurezahl - Potentiometrische Titration in nicht-wäßrigen Medien

Diese Europäische Norm legt ein Verfahren fest zur Bestimmung der Säurezahl durch potentiometrische Titration von Schmierölen und Mineralölzusätzen, die in Mischungen von Propan-2-ol, Dimethylsulfoxid und Toluol löslich sind. Dieses Verfahren gilt im Bereich von 0,1 mg KOH/g bis 250 mg KOH/g, und zwar für ungebrauchte und gebrauchte Schmieröle und Mineralölzusätze.

Produits pétroliers et lubrifiants - Détermination de l'indice d'acide - Méthode par titrage potentiométrique en milieu non aqueux

La présente norme européenne prescrit une méthode de détermination, par titrage potentiométrique, de l'indice d'acide des lubrifiants et des additifs solubles dans des mélanges de propan-2-ol, de diméthylsulfoxyde et de toluène. Elle est applicable dans la gamme de 0,1 mg KOH/g à 250 mg KOH/g, à des lubrifiants neufs et usagés ainsi qu'à des additifs d'huiles.

Naftni proizvodi in maziva – Določevanje kislinskega števila – Metoda z nevodno potenciometrično titracijo

General Information

• Status: Published
• Publication Date: 31-Oct-1999
• ICS: 75.080 - Petroleum products in general
• ICS: 75.100 - Lubricants, industrial oils and related products
• Technical Committee: NAD - Petroleum products, lubricants and related products
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 01-Nov-1999
• Due Date: 01-Nov-1999
• Completion Date: 01-Nov-1999
• Ref Project: EN 12634:1998 - Petroleum products and lubricants - Determination of acid number - Non-aqueous potentiometric titration method

Overview

EN 12634:1998 is a European Standard published by CEN that defines a non‑aqueous potentiometric titration method for determining the acid number (also called acid value) of petroleum products and lubricating oils and additives. The method applies to samples soluble in a solvent mixture of propan-2-ol (isopropanol), dimethylsulfoxide (DMSO) and toluene and covers a measurement range of 0.1 mg KOH/g to 250 mg KOH/g. It is intended for both unused and used lubricating oils and additives.

Key Topics

• Scope and applicability: Specifies which lubricants and additives the method covers and the soluble solvent system required.
• Measurement principle: Non‑aqueous potentiometric titration to quantify acidic components expressed as mg KOH per gram of sample.
• Measurement range: 0.1–250 mg KOH/g, suitable for trace to high-acidity samples.
• Sample types: Unused (fresh) and used (in-service) lubricating oils and oil additives that dissolve in the stated solvent mixture.
• Standardization and compliance: European Standard (CEN); reproduced regionally in national standards (e.g., SIST EN 12634:1999).
• Regulatory notes: The standard text is protected - reproduction of the full document without permission is not allowed.

Applications

EN 12634:1998 is used wherever accurate determination of acid number is needed to assess oil condition, compatibility and degradation:

• Lubricant quality control in manufacturing and blending operations.
• Used oil analysis for condition monitoring, maintenance decisions and failure analysis.
• Additive evaluation to determine acidic components in commercial additive packages.
• Research and development in formulation of industrial oils and specialty lubricants.
• Regulatory and procurement specifications where a recognized European method is required.

Keywords: EN 12634:1998, acid number, acid value, potentiometric titration, non‑aqueous titration, lubricating oils, additives, propan-2-ol, dimethylsulfoxide, toluene, mg KOH/g, used lubricating oils.

Who uses this standard

• Quality control laboratories in petroleum and lubricant industries
• Automotive, industrial maintenance and oil analysis service providers
• R&D teams developing lubricants and additive packages
• Procurement and compliance specialists specifying test methods

Related Standards

EN 12634:1998 sits among methods for acid number determination and is commonly referenced alongside other international and national potentiometric titration methods for petroleum products and lubricants. For implementation, refer to your national standards body for the official published text and any updates or equivalent documents.

Standards Content (Sample)

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Mineralölerzeugnisse und Schmierstoffe - Bestimmung der Säurezahl - Potentiometrische Titration in nicht-wäßrigen MedienProduits pétroliers et lubrifiants - Détermination de l'indice d'acide - Méthode par titrage potentiométrique en milieu non aqueuxPetroleum products and lubricants - Determination of acid number - Non-aqueous potentiometric titration method75.100MazivaLubricants, industrial oils and
...