view:29487 Last Update: 2018-2-14
Parvaneh Nakhostin Panahi
MnOx Catalysts Supported on γ-Al2O3, ZSM-5 and SAPO-34: Effect of Support on the Activity of Mn Supported Catalysts in NO Abatement by NH3
The NH 3–SCR of NO reaction has been studied using three different manganese containing catalysts supported on γ-Al2O3, ZSM-5, and SAPO-34. The nanocatalysts were prepared by homogeneous deposition precipitation (HDP) method and characterized via BET, TEM, H2-TPR, and NH3-TPD analysis. The activity of the catalysts varied significantly depending on the type of the support. The Mn-ZSM-5 and Mn/γ-Al2O3 catalysts were more active for NO conversion than Mn-SAPO-34 catalyst. The no correlation was found between surface area, strength and amount of acid sites, and NO conversion of the catalysts. The results of H2-TPR revealed lower onset reduction temperatures of MnOx species in Mn-ZSM-5 and Mn/γ-Al2O3 compared with Mn-SAPO-34, indicating easily reducibility of MnOx species in these catalysts. The redox properties of catalysts are responsible for the SCR activity. The Mn-SAPO-34 catalyst contains low quantitative of access reducible MnOx species, which is followed by considerable decrease in the activity. The NO conversion ability of Mn-supported catalysts has been correlated with support structure.