Bench-scale WGS membrane reactor for CO2 capture with co-production of H2

This study investigated the water-gas shift reaction in a bench-scale membrane reactor (M-WGS), where three supported Pd membranes of 44 cm in length and ca. 6 μm in thickness were used, reaching a total membrane surface area of 580.6 cm2. The WGS reaction was studied with the syngas mixture: 4.0% CO, 19.2% CO2, 15.4% H2O, 1.2% CH4 and 60.1% H2, under high temperature/pressure conditions: T = 673 K, pfeed = 20–35 bar(a), pperm = 15 bar(a), mimicking CO2 capture with co-production of H2 in a natural gas fired power plant. High reaction pressure and high permeation of Pd membranes allowed for near complete CO conversion and H2 recovery. Both the membranes and the membrane reactor demonstrated a long-term stability under the investigated conditions, indicating the potential of M-WGS to substitute conventional systems.

► The water-gas shift reaction (M-WGS) was examined in a bench-scale membrane reactor. ► Mimicking NGCC conditions for CO2 capture: T = 673 K, pfeed/pperm up to 35/25 bar(a). ► Near complete CO conversion and H2 recovery were achieved. ► A long-term stability both for the membranes and the membrane reactor. ► M-WGS has a great potential to substitute conventional systems.