TY - JOUR
T1 - Vanadia-based SCR catalysts supported on tungstated and sulfated zirconia
T2 - Influence of doping with potassium
AU - Skotte, Johannes
AU - Boghosian, Soghomon
AU - Kustov, Arkady
AU - Fristrup, Peter
AU - Tsilomelekis, George
AU - Ståhl, Kenny
AU - Christensen, Claus Hviid
AU - Fehrmann, Rasmus
N1 - Funding Information:
The Center for Sustainable and Green Chemistry is sponsored by the Danish National Research Foundation. This work was supported by Energinet.dk (project PSO-FU5201). The authors thank MAX-lab, Sweden, for facilitating the high-temperature XRD measurements.
PY - 2007/10/25
Y1 - 2007/10/25
N2 - A series of vanadium-based SCR catalysts supported on sulfated or tungstated ZrO2 were synthesized and characterized by means of N2-BET, XRD, NH3-TPD and in situ Raman spectroscopy. The effect of potassium doping on the properties of vanadia species was studied in detail. A number of catalyst preparation parameters were examined, including the choice of precipitant, variation of carrier surface area, potassium poisoning, crystallinity, and ZrO2-phase composition. The results show that the catalyst structure and SCR activity are affected from the synthesis route by the support crystallinity and morphology, the surface composition, and the molecular configuration of the dispersed vanadates. It was observed that poisoning with potassium had a negligible effect on the surface vanadate species (especially the V{double bond, long}O stretching frequency observed by in situ Raman spectroscopy) if supported on the sulfated zirconia. Conversely, a more pronounced influence on the structure of surface vanadate was observed for the corresponding unsulfated samples, in which a significant red shift in the V{double bond, long}O stretching frequency was observed on potassium doping. Computational studies suggested that potassium was responsible for both the observed decrease in V{double bond, long}O stretching frequency and the higher proportion of dimers and higher polymers through coordination between K+ and two neighbouring V{double bond, long}O. The results suggest an increased resistance toward potassium doping for the vanadia-based catalysts supported on sulfated zirconia.
AB - A series of vanadium-based SCR catalysts supported on sulfated or tungstated ZrO2 were synthesized and characterized by means of N2-BET, XRD, NH3-TPD and in situ Raman spectroscopy. The effect of potassium doping on the properties of vanadia species was studied in detail. A number of catalyst preparation parameters were examined, including the choice of precipitant, variation of carrier surface area, potassium poisoning, crystallinity, and ZrO2-phase composition. The results show that the catalyst structure and SCR activity are affected from the synthesis route by the support crystallinity and morphology, the surface composition, and the molecular configuration of the dispersed vanadates. It was observed that poisoning with potassium had a negligible effect on the surface vanadate species (especially the V{double bond, long}O stretching frequency observed by in situ Raman spectroscopy) if supported on the sulfated zirconia. Conversely, a more pronounced influence on the structure of surface vanadate was observed for the corresponding unsulfated samples, in which a significant red shift in the V{double bond, long}O stretching frequency was observed on potassium doping. Computational studies suggested that potassium was responsible for both the observed decrease in V{double bond, long}O stretching frequency and the higher proportion of dimers and higher polymers through coordination between K+ and two neighbouring V{double bond, long}O. The results suggest an increased resistance toward potassium doping for the vanadia-based catalysts supported on sulfated zirconia.
KW - Biomass
KW - DFT calculations
KW - Deactivation
KW - In situ Raman spectroscopy
KW - NO SCR with ammonia
KW - Potassium poisoning
KW - Sulfated zirconia
KW - Tungstated zirconia
KW - Vanadium oxide
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U2 - 10.1016/j.jcat.2007.07.016
DO - 10.1016/j.jcat.2007.07.016
M3 - Article
AN - SCOPUS:34748846255
SN - 0021-9517
VL - 251
SP - 459
EP - 473
JO - Journal of Catalysis
JF - Journal of Catalysis
IS - 2
ER -