Highly stable Ni-based catalysts derived from LDHs supported on zeolite for CO2 methanation

Abstract

CO2 methanation can effectively reduce the concentration of CO2 in the air and decrease environmental pollution. Therefore, it is essential to synthesize catalysts with high carbon deposition resistance and stability. Herein, the highly stabilized Ni-based catalysts derived from hydrotalcites are prepared by the self-sacrificial template method and used for CO2 methanation. The prepared Ni-based catalysts maintain the morphology of the hydrotalcites precursors and the Ni particles are embedded in the AlOx substrate. The catalyst show high performance at 350 °C, 0.1 MPa and a high space velocity of 30,000 mL g−1 h−1, with the conversion rate of CO2 and selectivity of CH4 reaching 87.5% and 100%, respectively. More importantly, the activity of catalyst does not decrease after continuous reaction for 200 h at 350 °C with different space velocities (30,000 and 60,000 mL g−1 h−1) owing to the confinement of the AlOx substrate, which suppress the undesirable agglomeration and sintering of the Ni particles. This unique mosaic structure has certain reference significance for studying materials with excellent stability at high temperatures.