Solvent extraction and separation studies of antimony(III) and bismuth(III) by using cyanex-925

Abstract

Cyanex-925 in xylene was used for extraction and separation of antimony(III) and bismuth(III) from aqueous solution. It was found that Sb(III) gets quantitatively extracted in the range 0.1-0.8 M HCl and 0.01-1.0 M H₂SO₄, while Bi(III) in the range 0.01-0.4 M HCl and 0.1-1.0 M HNO₃. From organic phase, Sb(III) was stripped back with 8.0 M H₂SO₄ and Bi(III) with 2.0-3.0 M HNO₃. The extraction behaviour of both the metal ions was studied separately as a function of acid concentration, temperature, equilibrium time and stripping ability using various acids and bases. Based on this results, sequential methods for their separation from multicomponent mixtures were developed.