view:28410 Last Update: 2018-2-14
Parvaneh Nakhostin Panahi, Gérard Delahay, Seyed Mahdi Mousavi
Activity of γ-Al2O3-based Mn, Cu, and Co oxide nanocatalysts for selective catalytic reduction of nitric oxide with ammonia
Our studies on the selective catalytic reduction of NO (SCR-deNO) properties of M/γ-Al2O3 (M = Mn, Co, Cu) nanocatalysts were presented. All catalysts were prepared by homogeneous deposition precipitation (HDP) using urea as the precursor for the precipitating agent. The SCR activity followed the order Mn/γ-Al2O3 > Cu/γ-Al2O3 > Co/γ-Al2O3. The nanocatalysts were characterized with respect to their texture (N2-BET), the particles size (TEM), reducibility (H2-TPR) and acidity (NH3-TPD). The TEM analysis revealed that the metal species have superior dispersion with less agglomeration and sintering on γ-Al2O3 support. The H2-TPR results confirmed that Mn/γ-Al2O3 nanocatalyst contain various oxidation states of manganese, which is useful for the catalyst to maintain the DeNO activities. The NH3-TPD studies indicated that the addition of transition metal can increase significantly the surface acidity and Mn/γ-Al2O3 showed the most adsorbed sites of NH3. Characterization results indicated that the acidity and the redox properties of the catalyst play important role in final catalytic activity at SCR-NO process.