# ISO 3771:1994 — Withdrawn and superseded ISO standards

For ISO 3771:1994, item title is Petroleum products — Determination of base number — Perchloric acid potentiometric titration method; status code is 9599; successor is ISO 3771:2011; withdrawn / published date is 1994-08-04, recorded from its source on 2026-08-05.

- **Identifier:** ISO 3771:1994 _(verified: appears in the quote below)_
- **Item title:** Petroleum products — Determination of base number — Perchloric acid potentiometric titration method _(verified: appears in the quote below)_
- **Status code:** 9599 _(verified: appears in the quote below)_
- **Successor:** ISO 3771:2011
- **Withdrawn / published date:** 1994-08-04 _(verified: appears in the quote below)_

## What the source says

> 21736,IS,,ISO 3771:1994,Petroleum products — Determination of base number — Perchloric acid potentiometric titration method,Produits pétroliers — Détermination de l'indice de base — Méthode par titrage potentiométrique à l'acide perchlorique,1994-08-04,2,['75.080'],ISO/TC 28,9599,[9291],[44771],['en'],8,"<p>Cancels and replaces the first edition (1977). Establishes a method for the determination of basic constituents in petroleum products by potentiometric titration with perchloric acid in glacial acetic acid. Two variations of the method are described, using different titration solvent volumes and test sample masses. The ranges of base number values for which precision values for the method

## Source

- https://isopublicstorageprod.blob.core.windows.net/opendata/_latest/iso_deliverables_metadata/csv/iso_deliverables_metadata.csv

Last verified: 2026-08-05. Review by: 2027-02-01.
Part of [Withdrawn and superseded ISO standards](https://referencesource.org/iso-standard-supersessions/).