Canadian Patent Application No.: CA 2552292
Abstracts
A process for the production of a purified PGM selected from the group consisting of platinum and rhodium from an impure PGM source, the process comprising (a) obtaining an anhydrous PGM halide from the impure PGM source; (b) treating the PGM halide with carbon monoxide at an effective temperature; pressure and time to form the PGM carbonyl halide; and (c)(i) wherein the PGM is platinum, heating the platinum carbonyl halide at an effective platinum decomposition temperature to produce the purified platinum; (ii) wherein the PGM is rhodium, heating the rhodium halide at an effective rhodium decomposition temperature to produce the purified rhodium; and (iii) wherein the platinum carbonyl carbonyl halide and the rhodium carbonyl halide are in a gaseous mixture, effecting step (i) at a temperature lower than the rhodium effective decomposition temperature prior to effecting step (ii). The process is of particular value in the recovery and recycle of PGM materials from vehicle exhaust catalytic converters.
