The mineral is broken down with a mixture of sodium carbonate and sodium peroxide, dissolved in water and filtered; sulfur passes in solution to the state of sodium sulphate. The filtrate is treated with hydrochloric acid and evaporated to dryness to insolubilize the silica, which is eliminated by filtration. In the filtrate obtained, sulfur is precipitated with barium chloride and dosed as barium sulphate. Reagent: picric acid solution. Method. Calculation.
UNI 3664-1955 history
1955UNI 3664-1955 Procedures for chemical analysis of minerals. Determination of sulphur in iron ore. Gravimetric method.