Effect of SO₂ and SO₃ Exposure to Cu-CHA on Surface Nitrate and N₂O Formation for NH₃-SCR.

ABSTRACT: We report effects of SO₂ and SO₃ exposure on ammonium nitrate (AN) and N₂O formation in Cu-CHA used for NH₃-SCR. First-principles calculations and several characterizations (ICP, BET, XRD, UV-vis-DRS) were applied to characterize the Cu-CHA material and speciation of sulfur species. The first-principles calculations demonstrate that the SO₂ exposure results in both (bi)sulfite and (bi)sulfate whereas the SO₃ exposure yields only (bi)sulfate. Furthermore, SOx adsorption on framework-bound dicopper species is shown to be favored with respect to adsorption onto framework-bound monocopper species. Temperature-programmed reduction with H₂ shows two clear reduction states and larger sulfur uptake for the SO₃-

SUBMITTER: Han J 

PROVIDER: S-EPMC11342297 | biostudies-literature | 2024 Aug

REPOSITORIES: biostudies-literature