Reference number
ISO 1389-7:1977
ISO 1389-7:1977
© ISO 2025
ISO 1389-7:1977
Phthalic anhydride for industrial use — Methods of test — Part 7: Determination of maleic anhydride content — Polarographic method
Edition 1
1977-02
1977-02
Withdrawn
Abstract
The principle consists in the dissolution of a test portion in acetone, removal of 1,4-naphthoquinone present in the solution by extraction with benzene. Polarographic measurement of the aqueous solution and determination of the mass of maleic anhydride by means of the calibration graph. - ISO 1389, Parts 1 to 11, replace ISO Recommendation R 1389-1970.