In-situ studies of oxidation/reduction of copper in Cu-CHA SCR catalysts: Comparison of fresh and SO2-poisoned catalysts
Artikel i vetenskaplig tidskrift, 2020

SO2-poisoning results in deactivation of Cu-CHA SCR under standard SCR conditions; however regeneration at 700 °C completely restores the SCR performance. To understand the nature of these effects, Cu-species in the fresh and poisoned catalysts were characterized by in-situ temperature-dependent time-resolved Cu K-edge X-ray absorption spectroscopy using the multivariate curve resolution alternating least squares (MCR-ALS) approach and continuous Cauchy wavelet transforms. The extracted chemically-meaningful reference spectra of Cu-species were analyzed by DFT-assisted XANES calculations. Cu-bisulfates were found as the most energetically favorable poisoned Cu-species. The response of Cu-species to a reducing environment differs in the fresh and SO2-poisoned catalysts. Differences in reducibility are related to the formation of quasi-linear Cu-complexes in the SO2-poisoned catalyst formed during heating in H2/He. Heating in H2/He leads to partial desulfurization of the poisoned catalyst. Cooling in H2/He after heating results in more facile formation of Cu-metal clusters in fresh catalyst than in SO2-poisoned.

SO /sulfur poisoning 2

NH -SCR 3

In-situ XANES

Cu-SSZ-13

regeneration

Författare

Susanna L. Bergman

Yale NUS College

Sandra Dahlin

Kungliga Tekniska Högskolan (KTH)

Vitaly V. Mesilov

Yale NUS College

Yang Xiao

Yale NUS College

Johanna Englund

Chalmers, Kemi och kemiteknik, Tillämpad kemi, Polymerteknologi

Shibo Xi

Institute of Chemical and Engineering Sciences, A-Star, Singapore

Chunhua Tang

Universiti Kebangsaan Singapura (NUS)

Magnus Skoglundh

Chalmers, Kemi och kemiteknik, Tillämpad kemi, Polymerteknologi

Lars J. Pettersson

Kungliga Tekniska Högskolan (KTH)

Steven L. Bernasek

Yale NUS College

Applied Catalysis B: Environmental

0926-3373 (ISSN) 1873-3883 (eISSN)

Vol. 269 118722

Ämneskategorier

Oorganisk kemi

Atom- och molekylfysik och optik

Annan kemi

DOI

10.1016/j.apcatb.2020.118722

Mer information

Senast uppdaterat

2020-11-30