| abstract |
A synthetic copper and/or iron containing zeolitic material having a CHA framework structure, wherein the CHA framework structure comprises SiO 2 ,X 2 O 3 , and optionally comprises Z 2 O 5 , wherein X is a trivalent element, and Z is a pentavalent element, wherein the zeolitic material contains from 3.8 to 12 wt.% of Cu and/or Fe calculated as the respective element and based on 100 wt.% of SiO 2 contained in the zeolitic material having a CHA framework structure, and wherein the 29 Si MAS NMR of the zeolitic material comprises: a first peak (P1) in the range of from -96 to -98.8 ppm; a second peak (P2) in the range of from -102 to -104.5 ppm; and a third peak (P3) in the range of from -107.5 to -111 ppm; wherein the integration of the first, second, and third peaks in the 29 Si MAS NMR of the zeolitic material offers a ratio of the integration values P1:P2:P3 ranging from (0.35-0.7):1: (0.1-1.6), as well as to a process for its preparation, and to the use thereof, in particular in a method for the selective catalytic reduction of NO x . |