The separation of mercury（Ⅱ）from other metal ions with the system of ammonium sulfate ammonium thiocyanate-Rhodamin B-water was studied.The results showed that with the amount of 1.0g (NH4)2SO4 and 0.5mL of the solution of 0.1mol/L NH4SCN and 1.0mL of the solution of 1.0×10-3mol/L RhB,Hg2+ could be floated quantitatively,and Cd2+,Cu2+,Mn2+,Co2+,Ni2+,Fe2+ and Al3+could not be floated,so Hg2+ could be separated successfully from those metal ions by flotation at pH 7.0.This method has been used for the flotation separation of Hg2+ in the sample of synthetic water and the results was satisfactory.
