Reference number
ISO 1388-7:1981
ISO 1388-7:1981
© ISO 2024
International Standard
ISO 1388-7:1981
Ethanol for industrial use — Methods of test — Part 7: Determination of methanol content (methanol contents between 0,01 and 0,20 % (V/V)) — Photometric method
Edition 1
1981-11
1981-11
ISO 1388-7:1981
5949
Published
(Edition 1, 1981)
This publication was last reviewed and confirmed in 2023.
Therefore this version remains current.
Abstract
The principle is based on the conversion of methanol present in a test portion to formaldehyde by oxidation. The oxidation is carried out with a solution of potassium permanganate in phosphoric acid. Reaction of the formaldehyde formed with chromotropic acid (4,5-dihydroxynaphthalene-2,7-disulphonic acid). Photometric measurement of the violet coloration obtained at a wavelength of about 570 nm. - International Standards ISO 1388/1 to ISO 1377/12 cancel and replace ISO Recommendation R 1388-1970 of which they constitute a technical revision.
Life cycle
-
Previously
WithdrawnISO/R 1388:1970
-
Now