Liquid-solid flotation separation of cadmium(II) by sodium chloride-potassium iodide-rhodamin B

The liquid-solid flotation separation of cadmium(Ⅱ) from other metal ions by sodium chloride-potassium iodide-rhodamin B was studied. The results showed that with the amount of 1.0 g NaCl and 1.0 mL of 0.1 mol/L KI and 1.5 mL of 1.0×10~(-3) mol/L RhB,Cd~(2+) was floated quantitatively,and Zn~(2+), Ni~(2+), Mn~(2+), Co~(2+), Al~(3+) was not floated. Cd~(2+) was thus separated successfully from those metal ions by flotation at pH 7.0. Under the optimum conditions, trace cadmium(Ⅱ) in the water samples was separated by flotation and determined by spectrophotometry with satisfactory results.