Pt dissolution and deposition in high concentration aqueous tri-iodide/iodide solutions

Abstract

The feasibility was demonstrated of Pt dissolution in neutral aqueous iodide / tri-iodide solutions, albeit requiring elevated temperatures, and of Pt electrodeposition from such solutions on to carbon, the cathode material to be used in the envisaged scaled process. Reduction of PtI62-(aq) was facile, producing PtI42-(aq) as a stable intermediate that could be further reduced to Pt by a much slower reaction. This system could form the basis of an environmentally benign, energy efficient process for the selective recovery of Pt from secondary materials. It is of importance that efficient recovery processes for strategic materials be developed as demand increases. © 2013 The Electrochemical Society.