Study on the Liquid-Solid Flotation Separation of Cadmium by Ammonium Sulfate-Potassium Iodide-Cetylpyridine Chloride-Water System

The liquid-solid flotation separation behaviors of Cd2+ in ammonium sulfate-potassium iodide-cetylpyridine chloride-water system and the conditions for the separation of Cd2+ from other metal ions were studied. The results showed that in the presence of 1.0 g (NH4)(2)SO4 and when the dosage of 0.1 M potassium iodide was 2.0 mL and 0.01 M cetylpyridine chloride (CPC) solution was 1.0 mL respectively, the formed water-insoluble ternary association complex of KI-CPC-Cd floated above water phase and liquid-solid phases were formed with clear interface. In this condition, Zn2+, Mn2+, Fe2+, Co2+, Ni2+ and Al2+ could not be floated and Cd2+ was floated quantitatively at pH 5.0. Therefore, the quantitative separation of Cd2+ from the above metal ions could be achieved. The quantitative flotation separation determination of Cd2+ in the sample of synthetic water and industrial waster water was performed, and the results agreed well with those by AAS method. The recoveries were 97.2%similar to 102.4%, and the RSD was 1.8%.