Separation of Mercury with an Ammonium Sulfate‐Ammonium Thiocyanate‐Ethyl Violet Flotation System

The separation behavior of mercury by a flotation system consisting of ammonium sulfate, ammonium thiocyanate and ethyl violet, and the conditions for the separation of Hg(II) with other common metal ions have been studied. The studies show that in aqueous solutions, Hg(II) combines with NH₄SCN and ethyl violet(EV) into dissoluble ternary ion‐association complex Hg(SCN)4^2?]?(EV)₂. In the presence of ammonium sulfate, the precipitate is floats well on the surface of the water phase and separates from water thoroughly. It shows that Hg(II) can be separated completely from Cd(II), Fe(II), Co(II), Ni(II), Mn(II) and Al(III) by flotation at pH1.0. The flotation mechanism of Hg(II) is described in this paper.