TY - JOUR
T1 - Plasma-enhanced catalytic reduction of SO2
T2 - Decoupling plasma-induced surface reaction from plasma-phase reaction
AU - AlQahtani, Mohammad S.
AU - Wang, Xiaoxing
AU - Knecht, Sean D.
AU - Bilén, Sven G.
AU - Song, Chunshan
N1 - Funding Information:
This paper is dedicated in honor of the late Professor Maria Stephanopoulos. One of the authors (MSQ) gratefully acknowledges the PhD scholarship from Saudi Aramco. This work is financially supported by the Pennsylvania State University and EMS Energy Institute Seed Grant .
Publisher Copyright:
© 2020
Copyright:
Copyright 2021 Elsevier B.V., All rights reserved.
PY - 2021/6/5
Y1 - 2021/6/5
N2 - Complex processes take place when coupling nonthermal plasma with heterogenous catalysis, obscuring mechanistic understanding of the plasma–catalysis synergy. Simultaneous homogenous plasma-phase reactions and heterogenous surface catalytic reactions occur in the system, which makes distinguishing the plasma's contributions very challenging. In this work, we perform a careful and rigorous evaluation of surface reactions under plasma conditions. We use SO2 hydrogenation as a probe reaction to examine plasma-induced surface reactions, desorption, and dissociation of SO2 adsorbate. A temperature-programmed plasma-induced surface reaction approach is used to decouple plasma-induced surface reactions from plasma-phase reactions. The qualitative and quantitative analyses reveal a new Eley-Rideal reaction between plasma-generated atomic hydrogen in the gas-phase and strongly adsorbed SO2 over alumina, a reaction that is not thermally feasible. Furthermore, plasma causes partial desorption of weakly adsorbed SO2 species and enhances the strong chemisorption of SO2 over supported iron sulfide catalyst. Moreover, plasma facilitates H2 chemisorption and reaction with iron sulfide, producing sulfur vacancies. This work sheds light on the possible origin of plasma–catalysis synergy and offers fundamental insight about the underlying mechanisms of plasma-assisted SO2 hydrogenation reaction.
AB - Complex processes take place when coupling nonthermal plasma with heterogenous catalysis, obscuring mechanistic understanding of the plasma–catalysis synergy. Simultaneous homogenous plasma-phase reactions and heterogenous surface catalytic reactions occur in the system, which makes distinguishing the plasma's contributions very challenging. In this work, we perform a careful and rigorous evaluation of surface reactions under plasma conditions. We use SO2 hydrogenation as a probe reaction to examine plasma-induced surface reactions, desorption, and dissociation of SO2 adsorbate. A temperature-programmed plasma-induced surface reaction approach is used to decouple plasma-induced surface reactions from plasma-phase reactions. The qualitative and quantitative analyses reveal a new Eley-Rideal reaction between plasma-generated atomic hydrogen in the gas-phase and strongly adsorbed SO2 over alumina, a reaction that is not thermally feasible. Furthermore, plasma causes partial desorption of weakly adsorbed SO2 species and enhances the strong chemisorption of SO2 over supported iron sulfide catalyst. Moreover, plasma facilitates H2 chemisorption and reaction with iron sulfide, producing sulfur vacancies. This work sheds light on the possible origin of plasma–catalysis synergy and offers fundamental insight about the underlying mechanisms of plasma-assisted SO2 hydrogenation reaction.
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U2 - 10.1016/j.apcatb.2020.119852
DO - 10.1016/j.apcatb.2020.119852
M3 - Article
AN - SCOPUS:85099628421
SN - 0926-3373
VL - 286
JO - Applied Catalysis B: Environmental
JF - Applied Catalysis B: Environmental
M1 - 119852
ER -