EXTRACTION OF Pd(II), Ni(II), Co(II), Cu(II), Fe(III) AND Zn(II) IONS WITH 1,2,3-BENZOTRIAZOLE IN SYSTEMS BASED ON ANIONIC SURFACTANTS

Abstract

The phase state and extraction capacities of aqueous systems based on sulfonol, sodium dodecylsulfate or alkylbenzenesulfonic acid as anionic surfactants and hydrochloric (or sulfuric) acid against the influence of 1,2,3-benzotriazole as an organic complexing reagent were studied. Introduc-tion of 1,2,3-benzotriazole into the systems resulted in its exfoliation in two liquid phases. Optimal concentration parameters of the extraction process in the systems under investigation were found: the total volume of the system (10 ml) contained sulfonol or sodium dodecyl sulfate (0.6 g), alkylbenzenesulphonic acid (0.5 g), and 1,2,3-benzotriazole (0.35 g). The aliquation state was maintained in the following concentration interval of HCl (H2SO4), mol L-1, for the systems with: (a) sodium dodecylsulfate: 0.5-6 (0.5-4), (b) sulfonol: 0.1-4 (0.05-3), (c) alkylbenzenesulfonic acid: 0-4 (0-3). Distribution of 0.01 mol L-1 of Pd(II), Ni(II), Cu(II), Co(II), Zn(II) and Fe(III) ions in the above systems was studied at the optimal components ratios. In the systems containing sodium dodecylsulfate, no quantitative extraction of metal ions was observed. In the systems with sulfonol and alkylbenzenesulfonic acid, practically complete (99.9%) extraction of palladium appeared to be possible in the entire range of acid concentrations; with minimal acid content, over 95% of copper and nickel were extracted. The extraction of palladium ions in the presence of interfering ions was studied. Quantitative recovery of palladium ions was found to not be obstructed by 500-fold molar excess of copper, 300-fold excess of cobalt and 70-fold excess of nickel.