Platinum, palladium, rhodium, iridium, ruthenium and osmium are chemical elements grouped together as the platinum group metals (PGMs). They have similar physical and chemical properties, generally derived from the same types of ores in which they occur together. Their main use is as catalysts within chemical industry and transportation exhaust systems, as well as green energy systems like water electrolysis for hydrogen production and fuel cells. PGMs have always been classified as critical raw materials (CRM) by the EU, due to their scarcity and the dependency on imports from outside the European region. In the latest criticality assessment, the supply risk increased for all the PGMs, but particularly for Ir. As part of the CRM strategy, the recovery of these valuable elements from secondary material streams like end-of-life (EoL) products and waste is encouraged. This is also in good harmony with the goals of the circular economy and zero-waste societies.
The efficient and selective extraction of PGMs, and especially of Ir and Ru, from different waste streams is challenging, mainly due to their inertness. They also tend to form passive oxidic compounds if exposed to traditional metal extraction methods, which prevents their effective recovery. This project will focus on the optimization of an innovative method that may circumvent these issues, achieving good extraction efficiencies without penalizing the purity of the recovered material and/or the environmental footprint. The project will further bring more knowledge to a field where there are large uncertainties regarding best practices.
One of the main emerging technologies utilising these elements is green hydrogen production from water electrolysis, where 1 MW proton exchange membrane (PEM) electrolyser requires about 1.5 kg of Ir. With the ambitious plans for expansion of this industry, recovery of valuable PGMs from EoL membrane electrode assembly is crucial and will be a focus in this project.
The main objective is to demonstrate an innovative efficient, and environmentally friendly extraction process to recover critical and valuable Ir, Ru and other PGMs from waste streams, especially from Hystar's electrolysers, into intermediates for KARʼs processing.
SINTEF takes the responsibility of developing, and further optimizing the technology to recover Ir , Ru and other valuable PGMs (Pt, Pd) from waste streams. The project allows SINTEF to increase its competence in the field of recovery of precious metals from secondary resources and valorization of waste streams.
