Hydrothermal synthesis of nanostructured Ce1-xNixO2-δ catalyst for the methanation of CO2

Carbon dioxide is the principal greenhouse gas produced by fossil fuels combustion. The CO2 methanation (Sabatier reaction) CO2 + 4H2 → CH4 + 2H2O combines the valorisation of CO2 with the storage of surplus energy by renewable sources (solar, wind), in the power to gas process (PtG). The present work uses ceria nanorods as support for metallic nickel. The Ce1-xNixO2-δ catalysts with different nickel content (x = 0.05; 0.10; 0.20; 0.30) were prepared by hydrothermal synthesis. Catalysts have been characterized by XRD, BET, H2-TPR, H2-TPD, FESEM, with the aim to verify the structure–sensitivity of the methanation on nickel. The catalytic activity and selectivity were studied using different CO2:H2 molar ratios, under atmospheric pressure, in the temperature range 200–500°C and gas hourly space velocity (GHSV) 300.000 cm3 h-1 g-1. The stability tests were performed at 400°C and GHSV 300.000 cm3 h-1 g-1 under fluctuating reaction conditions.