Keywords: platinum recovery, PGM, platinum group metals, spent catalysts, leaching, solvent extraction, TOPO, tri–octyl phosphine oxide, kerosene, hydrometallurgy, waste management, iron, automobile industry, materials recovery, metal recovery, spent catalytic converters, automotive materials, recycling
Automotive spent catalysts treatment and platinum recovery
The recovery of platinum from spent catalysts was examined. Platinum leaching was studied considering particle size, temperature, solid–liquid and HCl/HNO3 ratio effects. Many elements together with Pt were taken from a mixed spent catalyst sample. The main components of the leach liquor were Pt (1.84 g/kg cat) and Fe (0.94 g/kg cat). Platinum was separated from the leach aqueous solution by using Tri–Octyl Phosphine Oxide (TOPO) in kerosene. The extraction was studied considering equilibrium time, TOPO and HCl concentration, tin(II) chloride presence and stripping agents. Iron represents the main ion competitor for Pt extraction.