Nickel alloys Determination of phosphorus content Molybdenum blue molecular absorption spectrometric method

Available format(s)

Hardcopy , PDF , PDF 3 Users , PDF 5 Users , PDF 9 Users

Language(s)

English, French

Published date

08-27-1992

Publisher

International Organization for Standardization

Phosphorus content can be determined in the range of 0,001 % (m/m) to 0,025 % (m/m). Cr(III) and silica cause interference which is eliminated. The principle is dissolution of a test portion in a mixture of nitric and hydrochloric acids, fuming with sulfuric acid, oxidation of Cr(III) to Cr(VI), precipitation of Fe(III) phosphate and redissolution of the precipitate, addition of boric, tartaric and sulfamic acids, formation and extraction of molybdophosphoric acid, reduction of the heteropoly acid to molybdenum blue and back-extraction into an aqueous phase, measurement of the absorbance of the aqueous solution at 700 nm.

DevelopmentNote	Also numbered as BS 6783-12(1992) (04/2005)
DocumentType	Standard
Pages	6
PublisherName	International Organization for Standardization
Status	Current

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