Decomposition of N2O by Ruthenium Catalysts – RuO2 as Active Phase on Non‐Reducible Supports

Ruthenium has been supported on specifically chosen non‐reducible supports (Al2O3, SiO2, Al2O3‐SiO2 mixed oxides, Mg/ZnAl2O4 spinel, and AlF3), and these catalysts have been tested in the decomposition of nitrous oxide, N2O, to identify the catalytically active phase of ruthenium. Pure, bulk ruthenium dioxide, RuO2, and isolated Ru surface complexes have been synthesized and investigated for comparison. The catalysts were characterized by X‐ray diffraction, H2 chemisorption, N2 physisorption, temperature‐programmed reduction, and desorption TPR/TPD), andin situ infrared spectroscopy (IR). All aimed experiments strongly indicate that the decomposition of N2O occurs on ruthenium dioxide, RuO2, instead of metal particles. H2 pre‐reduction to Ru metal has inhibitory effects for all oxygen‐containing supports. The activity increases with the dispersion of ruthenium oxide. Bulk RuO2 showed the best catalytic performance.