Electrochemical hydrogen separation and compression using polybenzimidazole (PBI) fuel cell technology

Simultaneous hydrogen separation and compression using high-temperature (>100 °C) PEM fuel cell technology (PBI) was demonstrated for pure hydrogen, nitrogen/hydrogen mixtures and reformate feed gas mixtures containing various amounts of CO, CO2 and CH4. Gas purity measurements of the separated gas were performed and significant reductions in impurities were achieved. The effects of hydrogen concentration, inlet gas humidification, operating temperature and air bleed on the cell performance were studied and hydrogen diffusion through the polybenzimidazole membrane was measured. The hydrogen separation required relatively low energy consumption and demonstrated good dynamic response. Simultaneous separation and compression of hydrogen up to 0.65 barg was demonstrated.