Synthesis and functionalization of SSZ-13 as NH3-SCR catalyst

Artikel i vetenskaplig tidskrift, 2014

Hydrothermal synthesis of Na-SSZ-13 using a low concentration of the structure-directing agent N,N,N-trimethyl-1-adamantanimonium hydroxide and functionalization of the SSZ-13 framework through the introduction of Cu and Fe via ion-exchange have been carried out. The prepared samples were characterized with XRD, SEM, UV-Vis, N2-sorption, XRF and NH3-TPD. It was found that relatively large iron oxide particles and well-dispersed cationic Cu2+ species are formed as a result of ion-exchange with iron and copper, respectively. Further, the catalytic activity for NH3 oxidation, NO oxidation and selective catalytic reduction of NOx with ammonia (NH3-SCR) was investigated both in absence and presence of water. The functionalization of the SSZ-13 structure enhances the catalytic activity for NH3-SCR significantly. Whilst the NH3-SCR activity is negligible for the Na-SSZ-13 sample, the Cu-SSZ-13 sample is highly active, especially at low temperatures, and for the Fe-SSZ-13 sample highest activity is shown at elevated temperatures.