PNNL

Abstract

A series of Cu,H/SSZ-13 and Cu,Na/SSZ-13 catalysts were synthesized, degreened and hydrothermally aged for use in the standard NH3-SCR reaction. Surface area/pore volume and XRD analyses were used to probe the textural properties of the catalysts. H2-TPR and EPR were utilized to quantitatively describe the various Cu species. NH3-SCR was tested at both a lower space velocity to probe the light-off behavior, and at a higher space velocity to generate data for kinetic analysis. Na+ co-cation addition was found to promote turnover rates of isolated Cu-ions at low reaction temperatures. However, this promoting effect is compromised by decreases in Cu exchange capacity and hydrothermal stability of the Cu,Na/SSZ-13 catalysts. The authors gratefully acknowledge the US Department of Energy (DOE), Energy Efficiency and Renewable Energy, Vehicle Technologies Office for the support of this work. The research described in this paper was performed in the Environmental Molecular Sciences Laboratory (EMSL), a national scientific user facility sponsored by the DOE’s Office of Biological and Environmental Research and located at Pacific Northwest National Laboratory (PNNL). PNNL is operated for the US DOE by Battelle. The authors gratefully appreciate fruitful discussions with CRADA collaborators Craig Dimaggio, Kiran Premchand, Vencon Easterling and Mike Zammit from Fiat Chrysler Automobiles (FCA).