Ammonia (NH₃) decomposition is a promising route for on-board hydrogen (H₂) production; however, equilibrium limitations and H₂ inhibition restrict the performance of conventional catalytic packed-bed reactors (PBRs). Here, a catalytic hollow fibre membrane reactor (HFMR) is presented as an effective strategy to overcome these challenges. The reactor consists of a multichannel α-Al₂O₃ hollow fibre support whose outer surface is coated with a defect-free Pd membrane (11–13 μm) via electroless plating, while a Ru/Na–NCX catalyst is packed on the shell side. Electroless plating kinetics showed a linear Pd growth rate of ~3.7 μm·h −1 , and H₂ permeation followed the temperature-dependent solution–diffusion mechanism. The Ru/Na–NCX catalyst contained highly dispersed Ru nanoparticles (~2.5 nm) that remained stable after reaction, while Na promoters stabilised the structure and regulated surface hydrogen coverage. Continuous H₂ removal enhanced NH₃ conversion beyond equilibrium limits within 300–450 °C, achieving 64.5% H₂ recovery at 450 °C. Process analysis for a 100 kW system confirmed feasibility with reduced catalyst demand and no downstream NH₃ purification, highlighting the potential of HFMRs for compact on-board H₂ generation.
Mazzone et al. (Mon,) studied this question.