摘要 |
A hydrogen generation system is disclosed that includes a fuel reforming reactor generating a hydrogen-rich reformate gas at a temperature greater than 150 C, a pressure swing adsorption (PSA) hydrogen purification unit that separates the reformate gas into a relatively pure hydrogen stream and an off-gas stream, and a catalytic reactor down stream of the PSA unit that converts carbon monoxide (CO) and hydrogen (H<SUB>2</SUB>) contained in the relatively pure hydrogen stream into methane (CH<SUB>4</SUB>) and water vapor (H<SUB>2</SUB>O). The method of purification involves generating a hydrogen-rich reformate gas at a temperature greater than 150 C in a fuel reforming reactor, separating the reformate gas into a relatively pure hydrogen stream and an off-gas stream in a pressure swing adsorption (PSA) hydrogen purification unit, and converting carbon monoxide (CO) and hydrogen (H<SUB>2</SUB>) contained in the relatively pure hydrogen stream into methane (CH<SUB>4</SUB>) and water vapor (H<SUB>2</SUB>O) in a catalytic reactor down stream of the PSA unit. The hydrogen can be further purified by including a secondary purification stage downstream of the PSA unit and the catalytic reactor wherein the secondary purification stage has a water adsorbent material bed that adsorbs the water vapor H<SUB>2</SUB>O and a hydrogen absorbent material downstream of the water absorbent material that absorbs hydrogen gas preferentially, thus concentrating the non-hydrogen components, such as CH<SUB>4</SUB>, into an exhaust stream that exits the bed, wherein the absorbed hydrogen gas is then desorbed to create an exiting very pure hydrogen stream.
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