Enhanced water gas shift processes for carbon dioxide capture and hydrogen production

With the increasing concerns on fossil fuel depletion, environment deterioration, and global warming, great efforts have been devoted to the concept of "hydrogen economy" and the mitigation of CO2 emission. Among different technologies, enhanced water gas shift processes have exhibited significant importance not only for the production of high purity H-2 but also for their efficient CO2 separtion. By highlighting the novel materials and practical applications, we present a state-of-art review on the enhanced water gas shift processes towards improved CO2 removal and H-2 production via Le Chatelier's principle. First, we discussed detailed utilization of membrane reactors based on assortments of H-2-permselective membranes with a particular emphasis on their advantages and weaknesses towards CO2 separation. We also introduced the unique development of solid CO2 adsorbents, followed by their potential applications for intermediate-CO2 capture. Furthermore, the integrated combination of membrane assisted/sorption enhanced WGS processes are featured in this promising field. Finally, we critically reviewed recent implementations and applications with challenges and outlooks on the basis of the current development.