Separation And Recovery Of Some Platinum Group Metals (PGMs) By Means Of Selective Photocatalytic Reduction

Kriek, R. J. ; Engelbrecht, W. J. ; Cruywagen, J. J.
Organization: The Southern African Institute of Mining and Metallurgy
Pages: 8
Publication Date: Jan 1, 1995
Selective photo reduction, using the semiconductor TiO2 under UV irradiation, has been investigated as a possible recovery and/or separation method for the PGM's rhodium, palladium and platinum. The effect of pH value and concentration of the sacrificial reducing agent (ethanol) on the rate of reduction of Rh (III), Pd (II) and Pt(IV) ions have been determined separately for these ions as well as for some mixtures. Conditions favourable for the reduction and adsorption (or precipitation) on TiO2 have been established. It has been found that already deposited Pt or Pd metal promotes reduction of Rh (III) ions at a pH value where it would not otherwise be reduced. A method for the separation of a mixture comprising Rh (III), Pd(II) and Pt (IV), based on photo reduction and adsorption on the TiO2, is proposed.
Full Article Download:
(1482 kb)