Catalysts for unlocking H2production from NH3: A process design perspective

NH3 cracking is gaining attention as a promising route for on-demand, carbon-free H2 production, particularly in off-grid or distributed energy applications. Nevertheless, its practical implementation hinges on the development of catalysts not only highly active, but also cost-effective and thermally efficient. Starting from the state-of-theart catalyst for NH3 decomposition (nickel-based), the most promising catalytic systems (ruthenium-based) are critically reviewed, with a focus on the interplay between catalyst activation energy, thermal duty and operating conditions. In view of discussing whether the implementation of noble-based catalysts can be practical or not, a technical analysis of the cracking furnace with different Ru-based catalytic systems is presented, referring to a decentralized application representative of compact yet industrially relevant units. The trade-off between technical and economic performance is quantified, with the aim of offering design guidelines for developing scalable NH3 cracking.