Canadian Patent Application No.: CA 2411796
A process for preparing a pure PGM (platinum group metal) from a material containing a plurality of PGM compounds, wherein the PGM is selected from the group consisting of Pt, Pd; Os; Ir, Ru, Rh and Re, and the process includes initially forming the PGM in activated form by reduction of PGM ions in aqueous solution at pH 6-8 by a reducing agent, referably, hydrogen. Subsequently, the activated PGMs are treated by (a) reacting the material with a gaseous reactant to produce a gaseous mixture. comprising at least a first volatile PGM complex having a first decomposition temperature and a second volatile PGM complex having a second decomposition temperature, the first decomposition temperature being lower than second decomposition temperature, and a first residue; (b)
separating the gaseous mixture from the first residue; (c) heating the gaseous mixture to the first decomposition temperature to produce a pure first PGM and a first volatile PGM complex-free gaseous mixture; (d) collecting the pure first PGM; (e) heating the first volatile PGM complex-free gaseous mixture to said second decomposition temperature to produce a pure second PGM axed a second gaseous mixture; (f) and collecting the pure second PGM. The process provides for the extraction and separation of PGMs in an efficacious, economic and environmentally safe manner from ores, slag, mattes and slurries.