The catalytic activity of Cu-Mn-CeO
x/Al
2O
3/Al alumite catalyst in the selective catalytic reduction of nitric oxide by supplementation with propene (SCR-C
3H
6) was investigated at temperatures ranging from 473 to 773 K. Oxygen was found to have different effects on NO
x removal at low and high temperatures. Introducing a small amount of oxygen could significantly promote the reduction of NO
x at low temperatures. However, at high temperatures, the increase in oxygen substantially depressed NO
x conversion. When oxygen exceeded the critical concentration point (
S > 1.0, i.e. a net oxidizing condition), there was an optimal reaction temperature for maximal NO
x conversion, which occurred at the temperature required for complete oxidation of propene. An increase in propene was always favorable in enhancing the reduction of NO
x over the entire temperature range.
View full abstract