Low-temperature selective catalytic reduction of NOx with NH3 over metal oxide and zeolite catalysts—A review

Catalysis for NOx abatement

Composite Titanium Dioxide Nanomaterials

Ceria modified MnOx/TiO2 as a superior catalyst for NO reduction with NH3 at low-temperature

Nickel-doped Mn/TiO2 as an efficient catalyst for the low-temperature SCR of NO with NH3: Catalytic evaluation and characterizations

TiO2-supported transition metal oxides (Mn, Cr, and Cu) for the SCR of NO with NH3 have been synthesized by wet impregnation. The adsorption and coadsorption of NH3, NO, and O2, in conjunction with in situ FT-IR spectroscopy, was used to elucidate the reaction mechanism as the samples were heated from 323 to 673 K. While Cr was the only transition metal that generated significant amounts of Bronsted acidity, strong Lewis acid sites were present over all of the materials. The peak strength corresponding to the δs(NH3) coordinated to Lewis acid sites decreased in the following order:  Ti > Mn > Cr ∼ Cu. Similarly, the peak strength corresponding to the δas(NH3) coordinated to Lewis acid sites decreased as follows:  Mn > Cr ∼ Cu. Exposing the catalysts to oxygen before the introduction of NO did not impact the adsorption of NO as nitrates on the catalysts, suggesting that labile lattice oxygen plays an important role in the formation of nitrates. Three types of nitrates were observed after the adsorption of ...

and Ettireddy P. Reddy

Papers

Identification of Surface Species on Titania-Supported Manganese, Chromium, and Copper Oxide Low-Temperature SCR Catalysts