Study on a novel hydrogen purification approach base on methane steam reforming process with CO-preferential oxidation and CO2 removal

Methane steam reforming reaction is a mature, simple, economic and promising way to produce hydrogen-rich syngas in industrial field. However, the extraction rate of hydrogen obtained by this process is not high enough. This study proposes a novel hydrogen purification approach based on methane steam reforming with CO-preferential oxidation and CO2 removal. The energy and exergy analysis are carried out and the benefits of the novel approach are examined from the aspects of power consumption, natural gas consumption, and hydrogen production rate. The results demonstrate that the new hydrogen production system with new hydrogen purification approach has an exergy efficiency of 82.57 % and can produce 0.364 kg/h of hydrogen with a purity of 95.1 % without hydrogen loss while consuming 1 kg/h of methane when the reaction temperature, pressure, and steam-to‑carbon ratio are 750 °C, 1.01 bar and 2.5, respectively. The hydrogen produced per unit mass of methane consumption reaches the maximum of 0.3696 kg(H2)/kg(CH4) at 1.81 bar. The higher purity hydrogen purified by the new hydrogen purification approach with low energy consumption under ambient pressure and low temperature can meet the feed gas requirements of the PEMFC.