Sodium fluoride primarily used for the production of aluminium — Determination of soluble sulphates content — Turbidimetric method
NORMA vydána dne 1.7.1976
Označení normy: ISO 3431:1976
Datum vydání normy: 1.7.1976
Počet stran: 3
Přibližná hmotnost: 9 g (0.02 liber)
Země: Mezinárodní technická norma
Kategorie: Technické normy ISO
Description / Abstract: Applicable to products having SO4 contents of more than 0.05 % (m/m). Covers the dissolution of the test portion in hydrochloric acid and evaporation in hydrochloric acid solution for drying. Dissolution of the residue in a hydrochloric acid solution. Measurement of the turbidity obtained by precipitation, under specified conditions, of barium sulphate using a spectrophotometer at a wavelength of about 470 nm or a photoelectric absorptiometer.