Sorption-enhanced water gas shift reaction for high-purity hydrogen production: Application of a Na-Mg double salt-based sorbent and the divided section packing concept

• Published in: Applied energy 2017-11, Vol.205, p.316-322
• Main Authors: Lee, Chan Hyun, Lee, Ki Bong
• Format: Article
• Language: English
• Subjects: CO2 sorption; Divided section packing; Double salt-based sorbent; High-purity hydrogen; Sorption-enhanced water gas shift reaction
• ISSN: 0306-2619; 1872-9118
• DOI: 10.1016/j.apenergy.2017.07.119

[Display omitted] •Na-Mg double salt-based sorbent was used for high-temperature CO2 sorption.•Divided section packing concept was applied to the SE-WGS reaction.•High-purity H2 was produced from the SE-WGS reaction with divided section packing.•High-purity H2 productivity could be further enhanced by modifying packing method. Hydrogen is considered a promising environmentally benign energy carrier because it has high energy density and produces no pollutants when it is converted into other types of energy. The sorption-enhanced water gas shift (SE-WGS) reaction, where the catalytic WGS reaction and byproduct CO2 removal are carried out simultaneously in a single reactor, has received considerable attention as a novel method for high-purity hydrogen production. Since the high-purity hydrogen productivity of the SE-WGS reaction is largely dependent on the performance of the CO2 sorbent, the development of sorbents having high CO2 sorption capacity is crucial. Recently, a Na-Mg double salt-based sorbent has been considered for high-temperature CO2 capture since it has been reported to have a high sorption capacity and fast sorption kinetics. In this study, the SE-WGS reaction was experimentally demonstrated using a commercial catalyst and a Na-Mg double salt-based sorbent. However, the SE-WGS reaction with a one-body hybrid solid, a physical admixture of catalyst and sorbent, showed poor reactivity and reduced CO2 sorption uptake. As a result, a divided section packing concept was suggested as a solution. In the divided section packing method, the degree of mixing for the catalyst and sorbent in a column can be controlled by the number of sections. High-purity hydrogen (