ScholarWorks@동국대학교

초록

This study investigates the separation performance of various hollow fiber membranes (HFMs) for hydrogen (H2) recovery from ammonia (NH3) cracking processes. Oxide-based (γ-Al2O3 and SiO2) and metal-based (Pd and Pd–Ag–Cu) thin films were deposited on α-Al2O3 HFM supports and exposed to H2, N2 and trace of NH3 gas at 450 °C and 0.5–2.0 bar. The separation factor was defined as the ratio of the H2 permeate flow rate to the N2 permeate flow rate (α H2/N2) and to the NH3 permeate flow rate (α H2/NH3). Results show that Pd-based HFMs have better H2 selectivity than oxide-based HFMs. The Pd–Ag–Cu/α-Al2O3 HFM had the highest H2-to-NH3 selectivity with a α H2/NH3 separation factor of 1.4 104 over the tested pressure range. Pressure dependence varied among HFM types, metal-based HFMs showed increased H2 selectivity at higher pressures. These results have big implications for developing advanced membrane-based gas-gas separation processes for H2 purification in proton exchange membrane (PEM) fuel cell (FC) applications. Pd-alloy HFMs, especially Pd–Ag–Cu, are shown to be good for high-selectivity H2 separation from NH3 cracking products. © 2025

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