5TH International Congress on Technology - Engineering & Science - Kuala Lumpur - Malaysia (2018-02-01)

Synthesis Of Efficient Scr Catalyst For Lean Burn Nox Emission Control

A series of reactive grinding catalysts were synthesized for lean burn NOx emission control. Manganese oxide catalysts with TiO2, SiO2, and Al2O3 were synthesized by reactive grinding method. The catalysts were characterized and catalytically tested for selective catalytic reduction (SCR) of NO with H2-LPG for low temperatures (50-500°C). All the supports used were of commercial grade. In this study the influence of surface area, support nature (acidic, basic), and crystalline phase were find out on SCR activity. XRD studies reveal the presence of titania and alumina supports. Silica support was amorphous in nature and clearly depicted in XRD results. However, the presence of MnO2 was confirmed on other supports by XRD. FT-IR results indicate the presence of acid sites are helpful for SCR activity of catalyst. XPS results revealed the presence of two types of manganese oxides, MnO2 (654.2 eV) and Mn2O3 (644.2 eV), on all the samples. The SCR performance of the supported Mn catalysts decreased in the following order: TiO2 > γ-Al2O3 > SiO2. Quantitative NO conversion with 100% N2 selectivity was achieved at 110°C with Mn supported on TiO2. TiO2-supported MnO2 catalysts showed more promising SCR activity than Al2O3- or SiO2-supported manganese oxide catalysts. Characterization techniques suggest that high surface concentration of MnO2, Lewis acid sites and redox properties are significant features for SCR performance at low temperature.
DEEPAK, PRATICHI, RAM