Reference number
ISO 3706:1976
ISO 3706:1976
© ISO 2024
International Standard
ISO 3706:1976
Phosphoric acid for industrial use (including foodstuffs) — Determination of total phosphorus (V) oxide content — Quinoline phosphomolybdate gravimetric method
Edition 1
1976-11
1976-11
ISO 3706:1976
9181
Published
(Edition 1, 1976)
This publication was last reviewed and confirmed in 2023.
Therefore this version remains current.
Abstract
Applicable to products whether or not they are homogeneous and whether or not they contain polyphosphoric acids. Specifies preliminary hydrolysis of the polyphosphoric acids by boiling in the presence of hydrochloric acid. The precipitation of the phosphoric acid is carried out in the form of quinoline phosphomolybdate in the presence of acetone. Filtration by a filter crucible, washing, drying and weighing of the precipitate.