ISO 906:1976

Hydrochloric acid for industrial use — Determination of sulphate content — Barium sulphate gravimetric method

The method is applicable to products having sulphate contents equal to or greater than 0,1 % (m/m). The principle consists in precipitation of the sulphates contained in a test portion as barium sulphate in diluted hydrochloric acid medium. Separation of the precipitate obtained and ignition of the residue in an electric furnace, amintained at (800 +- 25 ) °C, and weighing. Replaces ISO Recommendation R 906-1968.