| abstract |
Provided is a catalyst for selective catalytic reduction of NOx in a lean-burn exhaust gas comprising a 0.8 : 1.0 to 1.2 : 1.0 blend of a metal promoted aluminosilicate having a CHA structure and a metal promoted silicoaluminophosphate having a CHA structure, respectively, wherein the silicoaluminophosphate is characterized by a higher promotion metal loading compared to the aluminosilicate. |