Separation of Gold from Cu, Pt, Pd, Ni, Zn, Cd and Hg Using Triphenylarsine Oxide as an Extractant

摘要

A method is developed for extraction of gold(III) (75 - 300 μg) from hydrochloric acid solution with triphenylarsine oxide dissolved in toluene as extractant. Gold(III) is determined spectrophotometrically with stannous chloride. The extraction is quantitative from 1.5 - 1.9 M hydrochloric acid with 0.25% triphenylarsine oxide and an equilibration period of 30 s. The method permits separation of gold(III) from Cu(II), Pt(IV), Pd(II), Ni(II), Zn(II), Cd(II) and Hg(II) and its spectrophotometric determination in ayurvedic medicines. The recovery and relative standard deviation obtained are >99.0% and <1.0%.