A New Technology for the Processing of Precious Metal Containing Secondary Raw Materials

A new technology for the processing of secondary raw materials containing precious and Platinum Group Metals (PGMs) has been designed at the Laboratory of Heavy Metals at USTU. The technology is based on hydrometallurgical processing of the materials followed by sorption separation of the PGMs from the leach solution. Different versions of the technology can be realised depending on the type of processed material but the fundamentals are similar. Some parts of the technology can easily be integrated into existing flowsheets. The stage of sorption removal of platinum and palladium was tested on the site of the Joint Stock Company (JSC) "Uralelectromed" on pilot plant scale. A process was developed to obtain fine gold, silver, platinum and palladium. No waste is produced because all solutions are recycled. There are no gas emissions. Selective sorption of platinum and palladium from silver-containing solutions is possible even if the concentration ratio of silver to PGMs is one thousand to one. Sorption behaviour of the PGMs as a function of the bulk metal concentrations was studied. Recovery of 90-95% of platinum and 70-80% of palladium is possible.