STUDY ON THE FLOATATION OF Cu(Ⅱ) BY THE AQUASOLID SYSTEM OFAMMONIUM THIOCYANATE-RHODAMINE B-H₂O IN THE PRESENCE OF AMMONIUM SULFATE

The characteristics of separation of Cu(Ⅱ) ion by floatation in an aquo-solid system of NH4SCN-rhodamine B-H2O in the presence of solid (NH4)2SO4 and the conditions of separation of Cu(Ⅱ) from some other commonly encountered metal ions,e.g.Cd2+,Mn2+,Co2+,Ni2+,Al3+ and etc.were studied.The optimized amounts of reagents required in the floatation process were given as follows:① solid (NH4)2SO4:1.0 g;② 0.01 mol·L-1 NH4SCN solution:1.5 mL;③ 1×10-3mol·L-1 rhodamine B solution:2.0 mL and ④ total volume of the analyte before adding (NH4)2SO4:10.0 mL.Under the condition specified above,Cu(Ⅱ) in the solution was precipitated as the water insoluble ternary ionic association complex,(RhB)2Cu(SCN)4,and floated at the interface of aqua-solid phases,while those coexisting metal ions mentioned above remained in aqua phase.In its application to the determination of microamounts of copper in simulated water sample,the recoveries of copper by floatation enrichment achieved to an average of 101.4%.