Abstract
Time-resolved in situ IR was performed during selective catalytic reduction of NO with NH3 on supported V2O5-WO3/TiO2 catalysts to examine the distribution and reactivity of surface ammonia species on Lewis and Brønsted acid sites. While both species were found to participate in the SCR reaction, their relative population depends on the coverage of the surface vanadia and tungsta sites, temperature, and moisture. Although the more abundant surface NH4+,ads intermediates dominate the overall SCR reaction, especially for hydrothermally aged catalysts, the minority surface NH3,ads intermediates exhibit a higher specific SCR activity (TOF). The current study serves to resolve the long-standing controversy about the active sites for SCR of NO with NH3 by supported V2O5-WO3/TiO2 catalysts.
| Original language | English |
|---|---|
| Pages (from-to) | 15624-15627 |
| Number of pages | 4 |
| Journal | Journal of the American Chemical Society |
| Volume | 139 |
| Issue number | 44 |
| DOIs | |
| State | Published - Nov 8 2017 |
Funding
The authors acknowledge financial support from the Center for Understanding & Control of Acid Gas-Induced Evolution of Materials for Energy (UNCAGE-ME), an Energy Frontier Research Center funded by DOE, Office of Science, and Office of Basic Energy Sciences under grant DE-SC0012577. Part of the work including the DRIFTS was conducted at the Center for Nanophase Materials Sciences, which is a DOE Office of Science User Facility. The authors would like to express their appreciation to Dr. Chris Keturakis of Cummins Emission Solutions for many valuable comments.