Catalytic abatement of NOx: Chemical and mechanistic aspects

Manganese–niobium mixed oxide catalyst for the selective catalytic reduction of NOx with NH3 at low temperatures

“…After exposure to NH 3 , the catalyst surface was covered by several NH 3 species; but when NO + O 2 was introduced at 150°C, the bands due to NH 3 absorbed species diminished. The bands at 1604, 1204 cm À1 assigned to coordinated NH 3 …”

“…Selective catalytic reduction of NO x with NH 3 (NH 3 -SCR) has been used extensively for the removal of nitrogen oxides emitted from stationary sources, and the most widely used catalyst system is V 2 O 5 -WO 3 (MoO 3 )/TiO 2 [2,3]. This catalyst exhibits high NO x conversion at 300-400°C, and the SCR reactor should be located upstream of the particle removal device and desulphurizer to avoid reheating of the flue gas.…”

“…The addition of Nb to MnO x -CeO 2 was found to be very effective in improving the activity and N 2 selectivity due to the significant increase of the surface acidity [17,18]. In this study, a series of Mn-Nb oxide catalysts were prepared by a homogeneous precipitation method and were applied to low temperature NH 3 -SCR of NO x . Due to its optimal redox capability and high acidity, the Mn 2 Nb 1 O x catalyst calcined at 500°C showed high NO x conversion and N 2 selectivity, and is a potential candidate for the low temperature deNO x process.…”

Selective catalytic reduction of NO by NH3 over a Ce/TiO2 catalyst

“…The selective catalytic reduction (SCR) of NO x using ammonia or urea is a well-proven technique for NO x removal from stationary power stations and diesel engines [1][2][3][4][5]. The general reaction is: 4NO + 4NH 3 [6,7].…”

NO decomposition, storage and reduction over novel mixed oxide catalysts derived from hydrotalcite-like compounds

“…age/reduction (NSR) [2], selective catalytic reduction (SCR) of NO x with NH 3 and hydrocarbons (HCs) [5][6][7]. The SCR has been intensively investigated and a number of reviews have been published elsewhere [5][6][7][8], so this review paper will focus on the recent advances of the catalysts that are made of the normal transition metal oxides derived from hydrotalcite-like compounds (HTlcs) yet are effective in NO x direct decomposition, and NO x storage under lean-burn conditions.…”