Solvent extraction separation of gold with Cyanex 302 as extractant

A method has been developed for the extraction of gold(III) from hydrochloric solution with Cyanex 302 dissolved in toluene. The extraction was quantitative from 0.005-8.0 M HCl with 7.5 x 10(-4) M Cyanex 302 and an equilibrium period of 3.0 min. Gold(III) from the non-aqueous phase was stripped with 0.1 M Na2S2O3 and determined spectrophotometrically at 400 nm using stannous chloride method. The method is useful for separation of Au(III) from Cu(II), Ni(II), Pd(II), Pt(IV)and Fe(III) and was extended for the determination of Au(III) in Ayurvedic drug samples. The method is reproducible with a relative standard deviation of +/- 1.0 %.