Pyrometallurgical Recovery of Platinum Group Metals from Spent Automotive Catalysts: A Computational Approach

This chapter delves into the pyrometallurgical recovery of platinum group metals (PGMs) from spent automotive catalysts, focusing on the dissolution behavior of platinum nanoparticles in copper collectors during the smelting process. The study highlights the challenges posed by the sintering effects that encapsulate PGM nanoparticles, complicating their recovery. It employs computational modeling using the phase field method to investigate the dissolution kinetics of platinum nanoparticles under different scenarios. The research identifies key limitations in conventional phase field models, particularly the instability issues arising from high thermodynamic driving forces and the need for accurate input parameters. The study proposes a combined high driving force and stoichiometric phase field approach to overcome these limitations, enabling more accurate simulations under pyrometallurgically relevant conditions. The findings indicate that the encapsulation depth of platinum nanoparticles significantly affects their dissolution time, with partially encapsulated particles dissolving 50% more slowly than non-encapsulated ones. The chapter concludes by emphasizing the importance of advanced phase field models in studying small-scale dissolution phenomena and their potential to optimize the recycling efficiency of PGMs.