Enhanced Low-temperature CO2 Hydrogenation to Methane Over Co-Zn Oxides Catalysts.

In this work, Cox/ZnO catalysts with different CoZn mass ratios were prepared by hydrothermal and impregnation methods, demonstrating that Cox/ZnO exhibits excellent low temperature (<260°C) CO2 methanation activity and selectivity at reaction pressures as low as 0.5Mpa. In order to explain the reaction properties of Cox/ZnO at low temperature and low pressure, the physicochemical properties of the catalysts were characterized by H2-TPR, XRD, BET, XPS and CO2-TPD.The results show that, compared with pure Co3O4 and ZnO samples, when CoZn is involved in the catalyst, the interaction between CoZn improves the structural properties of the catalyst, increases the specific surface area, generates more oxygen vacancies in the Cox/ZnO catalyst, and promotes the activation of CO2.This makes the Cox/ZnO catalyst have excellent performance of CO2 methanation. At the reaction temperature of 260℃, the CO2 conversion of Co5/ZnO catalyst can reach 82.27%, and the selectivity of CH4 and CO are 99.53% and 0.047%, respectively. It remained stable for 50 hours. This work highlights the interaction between CoZn and will contribute to the development of more effective low temperature and low pressure CO2 hydrogenation catalysts. [ABSTRACT FROM AUTHOR]