• • Decreasing Si/Al ratio from infinity (S-1) to 60 (HZ60) increases isolated Co2+ sites, reducing complete N2O decomposition temperature by 80 °C (from ~500 °C to ~420 °C, as inferred).
• • Co/HZ60 exhibits excellent resistance to O2 and NO, critical for real-world nitric acid plant tail gases where these inhibitors are present.
• • The strong Co2+-zeolite interaction prevents oxidation to Co3+, preserving active sites and enhancing N2O adsorption/activation.
• • Impregnation method preserves zeolite structure, ensuring stable catalyst morphology and dispersion of Co species.