Ru partial replacement of Ni in La0.6Ca0.4NiO3/CeO2 precursor: Enhancing integrated CO2 adsorption and methanation in DFM with NO, H2O and O2 containing flue gas

This study investigates the impact of partially substituting Ni with increasing amounts of Ru on the integrated CO 2 capture and methanation (ICCU-methanation) efficiency of a new generation of Dual Function Materials (DFMs) derived from perovskite precursors. Several 20 % La 0.6 Ca 0.4 Ni 1-y Ru y O 3 /CeO 2 -type precursors (with y = 0–0.3) are prepared and the corresponding DFMs are obtained after their reduction at 450 °C (2 h). The samples are extensively characterized before and after catalytic tests using XRD, N 2 adsorption-desorption, H 2 -TPR, H 2 -TPD, STEM-EDS, XPS, CO 2 -TPD and H 2 -TPSR techniques. Characterization results revealed that doping with a small amount of Ru (y = 0.05) allows almost the complete accommodation of Ni and Ru into the perovskite structure. The resulting DFM shows enhanced active sites accessibility and interactions with the rest of component, without significantly diminishing textural properties and basic sites concentration for CO 2 adsorption. The increased proximity and interaction between CO 2 adsorption sites and active metal sites promote CH 4 formation, especially at low/intermediate temperatures, leading to methane yield improvements of up to 10 %. Additionally, the y = 0.05 sample demonstrates enhanced performance and stability under industrially relevant conditions (presence of NO, O 2 and H 2 O) than the Ru-free (y = 0) DFM, this aspect together with the low Ru content employed (0.48 wt%) highlights its potential for the operation under realistic industrial conditions. • Ru accommodation within perovskite limited to Ni substitutions by Ru below 10 %. • Ru enhances active sites accessibility and interactions with CO 2 adsorption sites. • CO 2 adsorption/methanation is improved at low/intermediate temperatures. • Bimetallic Ni-Ru DFM shows higher stability under realistic feed. • La 0.6 Ca 0.4 Ni 0.95 Ru 0.05 O 3 /CeO 2 -derived DFM is a promising, cost-effective option.