Advances in end-of-life treatment of solid oxide electrolysis cell stacks: Environmental and material criticality assessment

End-of-life (EoL) strategies for hydrogen energy devices remain underdeveloped, despite their critical role in defining the environmental and resource profiles of these emerging technological solutions. This is particularly important for solid oxide electrolysis cells (SOECs), which contain valuable and scarce materials. This study aims to fill the gap for reliable data on large-scale continuous processes for recycling hydrogen-related devices by designing and simulating an industrial-scale process for recycling solid oxide electrolysis cell (SOEC) stacks in Aspen Plus®. An environmental benchmarking analysis was conducted by comparing life cycle assessment (LCA) and material criticality analysis (MCA) results for the proposed recycling process against the conservative EoL strategy, which involves recycling stainless steel while landfilling other components. Benchmarking against conventional EoL treatments shows improvements in several categories, especially under scenario-based analyses of process hotspots. Incorporating nitric acid recovery and renewable electricity leads to impact reductions in categories such as climate change (>10 %), while MCA results show reductions of 40 % (SH2E indicator) and 8 % (GPR indicator). These results highlight the potential of SOEC-specific recycling to improve the sustainability of hydrogen technologies, while also underscoring the need for techno-economic assessment and pilot-scale validation for industrial adoption. • An end-of-life strategy for solid oxide cell stack is designed and simulated. • Over 70 % of the ceramic materials can be recovered with acceptable properties for cell production. • Energy is mainly consumed for stack dismantling, cell detaching, and thermal treatment of recovered ceramics. • Recovering nitric acid and using renewable electricity improves the environmental performance of the stack recycling process. • The end-of-life strategy notably enhances the material criticality performance of the technology.