Abstract

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.