Ferrous bromide sulfide

Precipitate flotation was shown to remove cadmium (as the sulfide) using hexadecyltrimethylammonium bromide (HTA) at a pH of S-9. The residual cadmium concentration was approximately 0.5 mg/L. Using adsorbing colloid flotation with ferrous sulfide and HTA at pH 9 resulted in residual cadmium concentrations of 0.003 mg/L. In an effort to eliminate the use of sulfide, cadmium hydroxide was floated with ferric hydroxide and HTA. The lowest residual was 0.010 mg/L at pH 12. This system, however, was very sensitive to ionic strength variations. Other studies removed cadmium precipitates with various systems over large ranges of pH by varying the coprecipitates and surfactants. ... 

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