Extractive separation of platinum from macroamounts of palladium using triphenylphosphine oxide and its successive spectrophotometric determination by the stannous chloride method

Abstract

Trialkylphosphine oxides extract more effectively chloride complexes of platinum than of palladium(II). Of the examined tributylphosphine (TBPO), trioctylphosphine (TOPO), and triphenylphosphine (TPPO) oxides the latter one makes possible best separation of these metals. The extraction of platinum with TPPO from solutions containing platinum and palladium unfavorably decreases with increasing palladium concentration. Using 0.1 M TPPO solution in dichloroethane, at HCl concentration 7.5 M, it is possible to separate 2–200 μg Pt/ml at a palladium concentration not higher than 10 mg/ml. Separation of platinum from macroamounts of palladium has been combined with spectrophotometric determination of platinum by means of stannous chloride. The method has been applied to the analysis of palladium for platinum content.