University of Hull logo

Low temperature plasma-catalytic NOx synthesis in a packed DBD reactor: effect of support materials and supported active metal oxides

Patil, B.S.; Cherkasov, N.; Lang, J.; Ibhadon, A.O.; Hessel, V.; Wang, Q.

Authors

B.S. Patil

N. Cherkasov

J. Lang

V. Hessel

Q. Wang

Abstract

The direct synthesis of NOx from N2 and O2 by non-thermal plasma at an atmospheric pressure and low temperature is presented, which is considered to be an attractive option for replacement of the Haber-Bosch process. In this study, the direct synthesis of NOx was studied by packing different catalyst support materials in a dielectric barrier discharge (DBD) reactor. The support materials and their particle sizes both had a significant effect on the concentration of NOx. This is attributed to different surface areas, relative dielectric constants and particles shapes. The nitrogen could be fixed at substantially lowered temperatures by employing non-thermal plasma-catalytic DBD reactor, which can be used as an alternative technology for low temperature synthesis. The γ-Al2O3 with smallest particles size of 250–160 μm, gave the highest concentration of NOx and the lowest specific energy consumption of all the tested materials and particle sizes. The NOx concentration of 5700 ppm was reached at the highest residence time of 0.4 s and an N2/O2 feed ratio of 1 was found to be the most optimum for NOx production. In order to intensify the NOx production in plasma, a series of metal oxide catalysts supported on γ-Al2O3 were tested in a packed DBD reactor. A 5% WO3/γ-Al2O3 catalyst increased the NOx concentration further by about 10% compared to γ-Al2O3, while oxidation catalysts such as Co3O4 and PbO provided a minor (∼5%) improvement. These data suggest that oxygen activation plays a minor role in plasma catalytic nitrogen fixation under the studied conditions with the main role ascribed to the generation of microdischarges on sharp edges of large-surface area plasma catalysts. However, when the loading of active metal oxides was increased to 10%, NO selectivity decreased, suggesting possibility of thermal oxidation of NO to NO2 through reaction with surface oxygen species.

Publication Date Oct 5, 2016
Journal Applied catalysis B : environmental
Print ISSN 0926-3373
Publisher Elsevier
Peer Reviewed Peer Reviewed
Volume 194
Pages 123-133
Institution Citation Patil, B., Cherkasov, N., Lang, J., Ibhadon, A., Hessel, V., & Wang, Q. (2016). Low temperature plasma-catalytic NOx synthesis in a packed DBD reactor: effect of support materials and supported active metal oxides. Applied catalysis. B, Environmental, 194, 123-133. https://doi.org/10.1016/j.apcatb.2016.04.055
DOI https://doi.org/10.1016/j.apcatb.2016.04.055
Keywords Plasma catalysis, Nitric oxides, Catalyst support, Support particle size, Supported active metal oxides
Publisher URL http://www.sciencedirect.com/science/article/pii/S0926337316303289
Copyright Statement © 2016, Elsevier. Licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0/
Additional Information This article is maintained by: Elsevier; Article Title: Low temperature plasma-catalytic NOx synthesis in a packed DBD reactor: Effect of support materials and supported active metal oxides; Journal Title: Applied Catalysis B: Environmental; CrossRef DOI link to publisher maintained version: http://dx.doi.org/10.1016/j.apcatb.2016.04.055; Content Type: article; Copyright: © 2016 Elsevier B.V. All rights reserved.

Files

Article.pdf (2 Mb)
PDF

Copyright Statement
© 2016, Elsevier. Licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0/



You might also like


Downloadable Citations