Facilitated Transport Membranes (FTMs) for Syngas Purification (CO2/H2)

Abstract

AbstractThe most widely used method for hydrogen (H2) production are gasification and reforming methods, which in combination with the water–gas shift reaction produces a gaseous mixture, primarily composed of hydrogen (H2) and carbon dioxide (CO2). For the separation of CO2 from this product stream, membrane technology is considered to be one of the most efficient process as compared to conventional technologies due to its high energy efficiency, compact module, and ease of operation. Among different types of membranes, facilitated transport membranes (FTMs) have emerged as the most promising technology for CO2 capturing processes because of their remarkable gas separation selectivity and high permeability. In this chapter, different syngas production methods combined with water–gas shift reaction and their product stream purification through FTMs were concisely described. A wide range of recently reported FTMs for the application of CO2/H2 separation in syngas purification have been critically reviewed, which include mobile carrier (MC) FTMs, fixed-site carrier (FSC) FTMs, ionic liquid (IL) membranes, poly (ionic-liquid) (PIL) IL membranes, hybrid filler based MMMs and their composite based FTMs. Moreover, a Robeson’s permeability-selectivity trade-off graph has been discussed in this literature for comparing the CO2/H2 separation performances of various FTMs. Lastly, future research directions have also been proposed for further development of FTMs in order to utilize this technology for CO2 capture in industrial scale H2 production processes.KeywordsCO2-selective facilitated transport membranesSyngas purificationMixed matrix membranes (MMMs)Composite membranesHydrogen (H2) purificationCO2/H2 separation