Nickel Catalysts Supported on Ce x Sm y Zr1−x−y O2-δ Complex for CO2 Methanation and its Kinetic Analysis

Abstract

CO2 methanation shows advantages in Power-to-Gas technologies using renewable energy. In this article, Sm doped Ce x Sm y Zr1−x−y O2-δ complex is prepared using a one-pot hydrolysis method and is used as support for the Ru-Ni catalyst. The CO2 methanation activity at high temperature, GHSV, and thermal stability is tested. The results show that Sm doping is unfavorable for low-temperature methanation activity, but improves the thermal stability with Sm doping amount of 10 mol%. The Sm doping significantly enhances the performance at high temperatures (>400 °C ) and high GHSV (> 10000 h−1). Five reaction rate equations with different adsorption expressions are applied for kinetic analysis. Low activation energies ranging between 50.1 kJ/mol and 53.2 kJ/mol are observed for different models, which are lower than reported Ni-based catalysts. The equation considering both CO2 and H2O adsorption achieves the best-fitting results.