A Brief Review of H₂S and Nitrogen-Based Contaminants from Biogas: Effects on Reforming Catalysts and SOFC Anodes

This paper provides a brief review of biogas contaminants, examining the impact of hydrogen sulfide (H₂S), nitrogen (N₂), and ammonia (NH₃) on catalytic reforming processes and Solid Oxide Fuel Cells (SOFCs) electricity generation. Biogas, produced through anaerobic digestion (AD), is a promising renewable energy source that can be upgraded into biomethane and reformed into H₂-rich syngas for SOFCs. Despite this, contaminants like H₂S found in biogas and biomethane cause critical issues such as catalyst poisoning, decreased electrochemical performance, and higher maintenance costs, while NH₃, potentially formed from N₂ during reforming, can lead to catalyst degradation and reduced SOFC performance, representing an underexplored contamination pathway. This review highlights the negative impacts of H₂S, N₂, and NH₃ on catalytic reforming and SOFCs, causing catalyst deactivation and performance loss, thus reinforcing the importance of developing advanced purification methods and sulfur-tolerant materials to improve renewable hydrogen (H₂) production and fuel cell durability.