N₂O Decomposition over K-Ce Promoted Co-M-Al Mixed Oxide Catalysts Prepared from Hydrotalcite-like Precursors

A series of mixed oxide catalysts with different composition of Co-M-Al and Co-M-Ce-Al (M=Zn, Ni, Cu) were prepared by co-precipitation method from hydrotalcite-like com-pounds. The experimental results revealed the catalytic activity of Co-Ni-Al is slightly higher than that of Co-Zn-Al and much higher than that of Co-Cu-Al for direct decomposition of N₂O. Moreover, addition of small amounts of CeO₂ improved the catalytic activity signif-icantly and made the decomposition temperatures at which the N₂O conversion was 50% and 90% (T₅₀ and T₅₀) both decreased 80 oC than those of Co-M-Al catalysts without CeO₂ added. Further, potassium-load also promoted the catalytic activity, and the decomposi-tion temperatures of T₅₀ and T₉₀ both decreased approximately 50 oC. It is significant for decomposing N₂O from industries and reducing carbon emission from atmosphere.