ISO 1983:1977

Nitric acid for industrial use — Determination of sulphated ash — Gravimetric method

The principle of the method consists inevaporation of a test portion in a platinum dish, conversion of the residue to sulphates by treatment with sulphuric acid; ignition in an electric furnace, controlled at (800 +- 25) °C, and weighing. Replaces ISO Recommendation R 1983-1971.