Stabilized microporous crystalline material, method for making same, and use thereof for selective

There is disclosed a microporous crystalline material comprising a crystal structure having building units of double-6-rings (d6r) and pore opening of 8-rings, wherein the material comprises a first metal chosen from alkali-earth group, rare-earth group, alkali group or mixtures thereof, and a second metal chosen from copper, iron or mixtures thereof, wherein the material has molar silica to alumina ratio (SAR) from 3 to 12, and is further steamed to enhance stability. Methods of making the crystalline material are also disclosed. There is also disclosed a method of selective catalytic reduction of nitrogen oxides in exhaust gas, comprising at least partially contacting the exhaust gases with an article comprising the disclosed microporous crystalline material.