| abstract |
The present invention relates to the use, for the reduction of oxidizing contaminating entities of the NO x type, in particular NO 2 , present in a gas to be purified, of a catalytic system comprising or composed of an oxide corresponding to the molar formulation:n nCe 1-y-z O 2-x M y N z ,n in which:n Ce is cerium, M is an element chosen from: Gd, Y, Sc, Sm, La, Pr, Nd, Er or Tb, y is between 0.01 and 0.4, N is an element having several degrees of valency chosen from: Ti, V, Cr, Mn, Fe, Co, Ni or Cu, z is less than 0.4, x is greater than 0.05. |