Study on Liquid-solid Flotation Separation and Determination of Mercury (Ⅱ) by Ammonium Sulfate-potassium Iodide-cetylpyrinium Bromide-water System

摘要

The liquid-solid flotation separation and determination behaviours of mercury (II) by ammonium sulfate-potassium iodide-cetylpyrinium bromide-water system was studied. The effects of different parameters, such as the dosages of KI and cetylpyrinium bromide (CPB), various salts and acidity on the flotation yield of Hg2+ were investigated. The results shown that in the presence of 1.0 g (NH4)2SO4 and when the dosage of 0.1 mol/L potassium iodide was 1.5 mL and 1.0×10-3mol/L cetylpyrinium bromide (CPB) solution was 1.0 mL, the formed waterinsoluble ternary association complex of (CPB)2(HgI4) floated above water phase and liquid-solid phases was formed with clear interface. On this condition, Zn2+, Mn2+, Ni2+, Co2+, Fe2+ and Al3+ could not be floated and Hg2+ could be floated quantitatively at pH7.0. Therefore, the quantitative separation of Hg2+ from the above metal ions could be achieved. The quantitative flotation separation determination of Hg2+ in the sample of synthetic water was performed. The flotation yield was 91.3%-107.2%.