Recyclability of Proton Exchange Membrane Electrolysers for Green Hydrogen Production

Renewed interest in green hydrogen energy due to its versatility and ability to decarbonise numerous economic sectors prompted research on the evaluation of sustainability of associated technologies. Proton Exchange Membrane (PEM) water electrolysis is a promising technology to produce hydrogen gas from water electrolysis using renewable power. However, PEM electrolysers use rare noble metals and other expensive materials. Furthermore, the availability and supply risks are additional concerns for the critical metals. Hence, this paper explores the review of the recycling process of end-of-life PEM electrolysers from the point of collection to the final material recovery and the potential reuse in the manufacturing process. Several studies have highlighted existing and novel recycling technologies for the different materials used in electrolyser components. Some of these methods include hydrometallurgy, pyrometallurgy, transient electrochemical dissolution, selective electrochemical dissolution, and acidic process. Overview of these processes and implication of recycling are presented here.