要約

Nitrous oxide, N₂O, is now recognized as an environmental pollutant. Methods to remove N₂O are relatively scarce and only a few studies have been reported. In the present work, N2O reduction was performed over mono and bimetallic carbon-supported catalysts. One potential advantage of such catalysts lies in the carbon-reducing properties, eliminating the need for the addition of an external reducing agent.
Carbon-supported Ni catalysts were tested and their activities and stabilities were compared with Ni−K bimetallic catalysts. A commercial activated carbon was used as catalyst support and the metals were introduced by the excess-solution impregnation method.
Catalyst performances were evaluated by temperature-programmed reaction and isothermal reaction at 350°C.
Impregnation of Ni resulted in a higher activity, lower onset reaction temperature and lower temperature required for reaching 100% conversion. In isothermal tests at 350°C, Ni catalysts presented poor stability, which was increased by K addition. The better performances obtained by co-impregnation of K revealed the strong ability of K for N₂O dissociative chemisorption and oxygen transfer.