Geochemical assessment of platinum group metals for phytomining

Abstract Phytomining is suggested as a technology to obtain platinum group metals (PGMs) nanoparticles from plants grown on the mineralized soils or tailings. Samples from North American Palladium (Canada) and gossans from Broken Hill (BH) (Australia) were studied to assess the possibility of using these PGM-rich samples as substrates for phytomining. The bioavailability of PGMs was indirectly assessed using geochemical procedures. The selective extractions showed that the highest available concentration of Pd is 5.38 ppm in BH gossan 1. The extraction of PGMs by ammonium acetate, fulvic acid or citrate-dithionite indicates natural availability to plants. The BH gossan 1 was the best of the five studied samples for phytomining of Pd due to available Pd concentration (> 2 mg/kg), low Electric Conductivity (