Overcoming oxidation-induced deactivation of Ni-based dual-function materials in integrated sequential carbon capture and methanation with Ni/CeO2 catalyst and “Na2O”/Al2O3 sorbent in adjacent beds

Researchers developed dual-function materials (DFMs) that combine CO2-capturing and methanation catalyst components to reduce carbon dioxide emissions and generate valuable methane in integrated sequential carbon capture and methanation. However, severe oxidation-induced deactivation (high reduction temperature requirements) limits the use of Ni-Na2O/Al2O3 DFM in O2-containing applications. Therefore, Ni-Na2O/CeO2 DFM is synthesized, as CeO2 lowers the reduction temperature. Nevertheless, it fails to produce CH4 due to the inability to desorb CO2 at methanation temperatures. A two-bed system, with Ni/CeO2 catalyst and Na2O/ Al2O3 sorbent in a catalyst-to-sorbent ratio of 2:8, captures an average of 0.1187 mmol CO2/gsorbent-catalyst and produces an average of 0.0727 mmol CH4/gsorbent-catalyst over ten cycles at 300 degrees C. This system shows that a separate catalyst-sorbent system is more suitable than a DFM for O2-containing applications. However, validation of the materials and reactor design requires the presence of high levels of steam in the CO2 capture feed gas for real-world applicability.