A new active zeolite structure for the selective catalytic reduction (SCR) of nitrogen oxides: ITQ7 zeolite

The activity of a new zeolite material, ITQ7, has been studied for the selective catalytic reduction (SCR) of NO. The pore topology of this material is similar to the structure of a beta zeolite, with a tridirectional system with 12-member rings. ITQ7 exchanged with copper or cobalt shows a catalytic behaviour very similar to a beta zeolite exchanged with copper or cobalt, probably due to its similar structure. The presence of oxygen, water, sulphur dioxide and NO2 has been studied, obtaining the best results at low oxygen concentration and in the absence of water and SO2. Nevertheless if NO2 is present in the reaction mixture, the maximum activity of the catalyst shifts towards higher oxygen concentration.