ISO 1618-1976 PDF

Full title and description

ISO 1618:1976 — Aluminium oxide primarily used for the production of aluminium — Determination of vanadium content — N‑Benzoyl‑N‑phenylhydroxylamine photometric method. Specifies a laboratory photometric procedure for measuring low levels of vanadium in alumina used in primary aluminium production.

Abstract

This standard defines a chemical/photometric method for determining vanadium in aluminium oxide (alumina) intended for aluminium production. The procedure involves oxidation of vanadium to the pentavalent state, formation of a coloured complex with N‑benzoyl‑N‑phenylhydroxylamine (BPHA), extraction of the coloured complex into an organic phase and photometric measurement near 524 nm. The method is intended for low vanadium concentrations and includes limits on interfering oxides.

General information

• Status: Withdrawn (withdrawal completed 4 February 2016).
• Publication date: 1 September 1976.
• Publisher: International Organization for Standardization (ISO).
• ICS / categories: 71.100.10 (materials for the production of primary aluminium / aluminium oxide).
• Edition / version: Edition 1 (1976).
• Number of pages: 4.

Scope

Applies to aluminium oxide (alumina) used primarily for the production of aluminium and covers a photometric method suitable for analyzing vanadium contents in the approximate range of 0.0003 % to 0.016 % m/m, provided certain interfering oxides (notably chromium and titanium oxides) are below specified limits. The procedure describes sample preparation, oxidation to vanadium(V), complex formation with BPHA, organic extraction and photometric measurement at about 524 nm.

Key topics and requirements

• Applicable analyte: vanadium in aluminium oxide (alumina).
• Applicable concentration range: approximately 0.0003 % to 0.016 % (m/m).
• Interference limits noted for chromic oxide and titanic oxide — method suitability depends on these being below specified concentrations.
• Oxidation step using potassium permanganate in sulfuric acid to convert vanadium to V(V).
• Formation of a vanadium–BPHA (N‑benzoyl‑N‑phenylhydroxylamine) coloured complex.
• Liquid–liquid extraction of the coloured complex into an organic solvent (chloroform) under controlled acidic conditions.
• Photometric (colorimetric) measurement of the extracted complex at around 524 nm and calibration against standards.
• Requirements for laboratory-grade reagents, glassware and reporting of results consistent with ISO chemical-analysis conventions.

Typical use and users

Used by analytical and quality‑control laboratories within alumina production plants, primary aluminium producers, independent testing laboratories and materials research groups concerned with the chemical quality of alumina feedstocks. Typical applications include incoming‑material QC, specification compliance checks and process troubleshooting where vanadium content influences downstream smelting performance or product quality.

Related standards

This standard is part of a cluster of ISO documents addressing aluminium oxide and materials used in primary aluminium production. Closely related documents include ISO 1617 (determination of sodium in alumina), ISO 802 (preparation and storage of test samples for aluminium oxide), ISO 803/804 (other chemical/physical test methods for alumina) and ISO 1619 (cryolite — preparation and storage of test samples). These companion standards cover sampling, sample preparation, alternative chemical determinations and other analytical techniques for materials used in aluminium production.

Keywords

aluminium oxide; alumina; vanadium determination; photometric method; N‑benzoyl‑N‑phenylhydroxylamine; BPHA; chloroform extraction; potassium permanganate oxidation; chemical analysis; primary aluminium feedstock.

FAQ

Q: What is this standard?

A: ISO 1618:1976 is an ISO method for determining vanadium content in aluminium oxide (alumina) used in the production of aluminium, using a BPHA photometric procedure.

Q: What does it cover?

A: It covers a laboratory photometric procedure: oxidation of vanadium to V(V), complexation with N‑benzoyl‑N‑phenylhydroxylamine, extraction into an organic solvent and measurement of the coloured complex at about 524 nm. It specifies the applicable vanadium concentration range and interference limits for certain oxides.

Q: Who typically uses it?

A: Quality control and analytical laboratories in alumina production and primary aluminium plants, independent testing facilities and researchers concerned with alumina chemistry and raw‑material quality.

Q: Is it current or superseded?

A: ISO 1618:1976 has been withdrawn (withdrawal process completed in early February 2016). The ISO catalogue does not list a direct replacement standard; users should consult current ISO/TC 226 publications and national/industry methods for up‑to‑date procedures.

Q: Is it part of a series?

A: Yes — it is one of a set of ISO standards dealing with aluminium oxide and related materials for primary aluminium production (for example ISO 1617, ISO 802, ISO 803, ISO 804 and ISO 1619), which together address sampling, sample preparation and a range of chemical and physical test methods.

Q: What are the key keywords?

A: Aluminium oxide, alumina, vanadium, photometric method, BPHA, chemical analysis, extraction, potassium permanganate.