Low-Temperature and High-Efficiency Catalytic Conversion N2O to N2 in the Presence of CO over Nonnoble Metal Cu–Fe Catalyst

Abstract

Nitrous oxide (N₂O) is a long-lived stratospheric ozone-depleting substance with an atmospheric lifetime of 116 years. It is also a greenhouse gas with a global warming potential value of about 310. Due to its high kinetic stability and thermal decomposition temperature exceeding 1000°C, the treatment and recovery of nitrous oxide pose significant engineering and climate challenges. In this study, we introduce a Cu–Fe oxide catalyst that demonstrates efficient and low-temperature conversion of N₂O to N₂ using readily available reductant CO. The oxide catalyst was synthesized by a solvothermal method and a “from bottom to top” technique. Characterizations by X-ray diffraction (XRD), CO temperature-programmed desorption (C-O‑TPD), scanning electron microscopy (SEM), and BET indicate that the catalyst with weaker CO adsorption sites, fewer strong CO adsorption sites, suitable particle size, good dispersion and high specific surface area performs excellent reaction activity in the reduction of N₂O to N₂ by CO. The active site of Cu is stronger, and the addition of Fe can promote dispersion of the Cu active site and increase the exposure to the active site. A new approach has been proposed to address nitrous oxide emissions, a greenhouse gas with high thermodynamic stability, in the chemical industrial process that generates nitrous oxide as a byproduct.