Publication
Title
Plasma-catalytic ammonia synthesis in a DBD plasma : role of microdischarges and their afterglows
Author
Abstract
Plasma-catalytic ammonia synthesis is receiving ever increasing attention, especially in packed bed dielectric barrier discharge (DBD) reactors. The latter typically operate in the filamentary regime when used for gas conversion applications. While DBDs are in principle well understood and already applied in the industry, the incorporation of packing materials and catalytic surfaces considerably adds to the complexity of the plasma physics and chemistry governing the ammonia formation. We employ a plasma kinetics model to gain insights into the ammonia formation mechanisms, paying special attention to the role of filamentary microdischarges and their afterglows. During the microdischarges, the synthesized ammonia is actually decomposed, but the radicals created upon electron impact dissociation of N-2 and H-2 and the subsequent catalytic reactions cause a net ammonia gain in the afterglows of the microdischarges. Under our plasma conditions, electron impact dissociation of N-2 in the gas phase followed by the adsorption of N atoms is identified as a rate-limiting step, instead of dissociative adsorption of N-2 on the catalyst surface. Both elementary Eley-Rideal and Langmuir-Hinshelwood reaction steps can be found important in plasma-catalytic NH3 synthesis.
Language
English
Source (journal)
The journal of physical chemistry: C : nanomaterials and interfaces. - Washington, D.C., 2007, currens
Publication
Washington, D.C. : 2020
ISSN
1932-7447 [print]
1932-7455 [online]
DOI
10.1021/ACS.JPCC.0C05110
Volume/pages
124 :42 (2020) , p. 22871-22883
ISI
000585970300002
Full text (Publisher's DOI)
Full text (open access)
Full text (publisher's version - intranet only)
UAntwerpen
Faculty/Department
Research group
Project info
Experimental and theoretical study of the fundamental mechanisms of nitrogen fixation by plasma and plasma-catalysis: towards the development of novel, environmentally friendly and efficient processes (NITROPLASM).
Surface-COnfined fast-modulated Plasma for process and Energy intensification in small molecules conversion (SCOPE).
Plasma catalysis at the nanoscale: A generic Monte Carlo model for the investigation of the diffusion and the chemical reactions of plasma species at porous catalysts.
Multi-scale modeling of plasma catalysis/
CalcUA as central calculation facility: supporting core facilities.
Publication type
Subject
Affiliation
Publications with a UAntwerp address
External links
Web of Science
Record
Identifier
Creation 01.12.2020
Last edited 17.12.2024
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