Enhanced activity of desilicated Cu-SSZ-13 for the selective catalytic reduction of NO x and its comparison with steamed Cu-SSZ-13

Mesoporous Cu-SSZ-13 was created by first synthesizing zeolite H-SSZ-13 and subsequently desilicating the material by base leaching using NaOH in different concentrations. The catalyst materials were prepared by ion exchanging the leached samples back to their acidic form using NH4NO3, and to their active Cu form by ion exchanging them with CuSO4. For comparison, H- and Cu-SSZ-13 were steamed using a wide variety of different conditions. Using a 0.10 M NaOH solution for base leaching, it was found that Cu-SSZ-13 becomes more active in the selective catalytic reduction of NOx with NH3 (NH3-SCR) over the entire temperature region but especially in the low temperature region (