Cu promoted Ni-Ca dual functional materials for integrated CO2 capture and utilization in O2-containing flue gas: Eliminating the delay in the utilization stage

Integrating CO2 capture and utilization by dry reforming methane (ICCU-DRM) technology is promising in concentrating and utilizing diluted CO2 from flue gas, which depends on developing Dual Functional Materials (DFMs) with adsorption and catalytic sites. Ni-Ca materials are widely applied in ICCU-DRM due to their excellent catalytic and CO2 adsorption properties. Nevertheless, the challenge remains that oxygen in the actual flue gas would oxidize the active Ni, leading to a delay in the DRM stage. In this work, Cu-promoted, ZrO2-stabilized Ni-Ca based DFMs were developed, which suppressed the delay and enhanced the performance of the DRM reaction. Attribute to the excellent reducing properties, Cu could be rapidly reduced in the CH4 atmosphere and further promote the reduction of NiO to the catalytically active Ni monomers by activating methane to generate reactive hydrogen (H*). What's more, attributed to the disappearance of delay times, it is accompanied by a satisfying yield distribution with a 0.11 decrease in H2/CO ratio and an improvement in conversion, especially CH4 conversion with an increase of more than 10%. In addition, the bifunctional material also exhibits favorable cycling stability due to the stabilizers.