Ion flotation of gold(III), platinum(II), palladium(II), and mercury(II) in hydrobromic acid with cationic surfactants

Abstract

Ion flotation of gold(III), platinum(II), palladium (II), and mercury(II) in hydrobromic acid solutions with cationic surfactants, tetradecyldimethylbenzylammonium chloride(TDBAC), cetylpyridinium chloride(CPC), and cetyltrimethylammonium chloride(CTMAC) was investigated. A 0.023.0 M hydrobromic acid solution (12 ml) containing (4.145.15)×10^-4 M of metal and (0.8941.39)×10^-3 M of surfactant was subjected to flotation in a 2.7(diameter)×20 cm, cell for 20 min with nitrogen bubbles. Gold(III), platinum(II), palladium(II), and mercury(II) were separated from the respective metal solution in 9499.5 % yield, while (2.277.93)×10^-4 M of Cu(II), Zn(II), Ni(II), Co(II), Mn(II), Fe(III), Al(III), Ga(III), In(III), Cr(III), and Sn(IV) were not floated from 0.1 M hydrobromic acid solution. The analysis of the relations between n (the mean number of the ligand Br^- per each metal) and the concentration of bromide by means of the mole ratio method, suggested the existence of the species such as AuBr₄^-, PtBr₃^-, PtBr₄^2-, PdBr₃^-, PdBr₄^2-, PdBr₅^3-, HgBr₃^-, and HgBr₄^2- in hydrobromic acid solution used for the flotation experiments.