Sibanye-Stillwater has teamed up with metals refining firm Heraeus to create a partnership which will develop new catalysts for the production of green hydrogen which are viewed as critical to the development of the sector.
The project is to be equally funded by the partners over a three year period and the results are to be mutually commercialised with the partners to co-operate on the marketing of the new catalyst.
The main aim is to replace the iridium used in electrocatalysts for the generation of green hydrogen by means of PEM (proton exchange membrane) electrolysis.
According to a joint statement from Sibanye-Stillwater and Heraeus “iridium is one of the scarcest pgms (platinum group metals) and its limited availability is a potential constraint on the future widespread adoption of pgm PEM electrolysers.
“Reducing iridium loadings in PEM electrocatalysts is key to ensuring a sustainable hydrogen ecosystem enabling PEM technology to be cost competitive to make triple digit, giga-watt scale a reality within the next decade.”
One possible alternative being looked at to use another pgm – ruthenium – which the partners say “offers significant potential” adding that they “aim to develop a new, robust solution based on looking at the substitution of iridium with other metals as well as developing more sophisticated metal oxide structures.”
Sibanye-Stillwater CEO Neal Froneman commented “our objective is to ensure our metals, including pgms, play a vital role in unlocking the future green economy including hydrogen. “
Heraeus executive vice-president Philipp Walter commented, “without cost-effective PEM electrolysis the targets for the ramp-up of the hydrogen economy cannot be achieved. We are ready to invest into a sustainable raw material strategy to make it happen.”
Heraeus – which is headquartered in Hanau, Germany – already has close links with the South African platinum industry. It refines the pgm concentrate output from Northam Platinum and from 2024 will refine 50% of the pgm concentrates produced by the Ivanplats’ Platreef mine which, in December last year, announced these concentrates would be sold to Northam.