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Author | Vermeiren, V.; Bogaerts, A. | ||||
Title | Supersonic Microwave Plasma: Potential and Limitations for Energy-Efficient CO2Conversion | Type | A1 Journal Article | ||
Year | 2018 | Publication | Journal Of Physical Chemistry C | Abbreviated Journal | J Phys Chem C |
Volume | 122 | Issue | 45 | Pages | 25869-25881 |
Keywords | A1 Journal Article; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ; | ||||
Abstract | Supersonic flows provide a high thermodynamic nonequilibrium, which is crucial for energy-efficient conversion of CO 2 in microwave plasmas and are therefore of great interest. However, the effect of the flow on the chemical reactions is poorly understood. In this work, we present a combined flow and plasma chemical kinetics model of a microwave CO 2 plasma in a Laval nozzle setup. The effects of the flow field on the different dissociation and recombination mechanisms, the vibrational distribution, and the vibrational transfer mechanism are discussed. In addition, the effect of experimental parameters, like position of power deposition, outlet pressure, and specific energy input, on the CO 2 conversion and energy efficiency is examined. The short residence time of the gas in the plasma region, the shockwave, and the maximum critical heat, and thus power, that can be added to the flow to avoid thermal choking are the main obstacles to reaching high energy efficiencies. |
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000451101400016 | Publication Date | 2018-11-15 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1932-7447 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.536 | Times cited | 5 | Open Access | Not_Open_Access |
Notes | Fonds Wetenschappelijk Onderzoek, G.0383.16N ; | Approved | Most recent IF: 4.536 | ||
Call Number | PLASMANT @ plasmant @c:irua:155412 | Serial | 5070 | ||
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Author | Vermeiren, V.; Bogaerts, A. | ||||
Title | Improving the Energy Efficiency of CO2Conversion in Nonequilibrium Plasmas through Pulsing | Type | A1 Journal article | ||
Year | 2019 | Publication | The journal of physical chemistry: C : nanomaterials and interfaces | Abbreviated Journal | J Phys Chem C |
Volume | 123 | Issue | 29 | Pages | 17650-17665 |
Keywords | A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Nonequilibrium plasmas offer a pathway for energy-efficient CO2 conversion through vibrationally induced dissociation. However, the efficiency of this pathway is limited by a rise in gas temperature, which increases vibrational−translational (VT) relaxation and quenches the vibrational levels. Therefore, we investigate here the effect of plasma pulsing on the VT nonequilibrium and on the CO2 conversion by means of a zerodimensional chemical kinetics model, with self-consistent gas temperature calculation. Specifically, we show that higher energy efficiencies can be reached by correctly tuning the plasma pulse and interpulse times. The ideal plasma pulse time corresponds to the time needed to reach the highest vibrational temperature. In addition, the highest energy efficiencies are obtained with long interpulse times, that is, ≥0.1 s, in which the gas temperature can entirely drop to room temperature. Furthermore, additional cooling of the reactor walls can give higher energy efficiencies at shorter interpulse times of 1 ms. Finally, our model shows that plasma pulsing can significantly improve the energy efficiency at low reduced electric fields (50 and 100 Td, typical for microwave and gliding arc plasmas) and intermediate ionization degrees (5 × 10−7 and 10−6). | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000477785000003 | Publication Date | 2019-07-25 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1932-7447 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.536 | Times cited | 1 | Open Access | |
Notes | Fonds Wetenschappelijk Onderzoek, G.0383.16N ; This research was supported by the FWO project (grant G.0383.16N). The calculations were performed using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen (UAntwerpen), a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI), and the UAntwerpen. We also like to thank N. Britun (ChIPS) for the interesting discussions. | Approved | Most recent IF: 4.536 | ||
Call Number | PLASMANT @ plasmant @c:irua:161621 | Serial | 5289 | ||
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Author | Vermeiren, V.; Bogaerts, A. | ||||
Title | Plasma-Based CO2Conversion: To Quench or Not to Quench? | Type | A1 Journal article | ||
Year | 2020 | Publication | Journal Of Physical Chemistry C | Abbreviated Journal | J Phys Chem C |
Volume | 124 | Issue | 34 | Pages | 18401-18415 |
Keywords | A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Plasma technology is gaining increasing interest for CO2 conversion. The gas temperature in (and after) the plasma reactor largely affects the performance. Therefore, we examine the effect of cooling/quenching, during and after the plasma, on the CO2 conversion and energy efficiency, for typical “warm” plasmas, by means of chemical kinetics modeling. For plasmas at low specific energy input (SEI ∼ 0.5 eV/molecule), it is best to quench at the plasma end, while for high-SEI plasmas (SEI ∼ 4 eV/molecule), quenching at maximum conversion is better. For low-SEI plasmas, quenching can even increase the conversion beyond the dissociation in the plasma, known as superideal quenching. To better understand the effects of quenching at different plasma conditions, we study the dissociation and recombination rates, as well as the vibrational distribution functions (VDFs) of CO2, CO, and O2. When a high vibrational−translational (VT) nonequilibrium exists at the moment of quenching, the dissociation and recombination reaction rates both increase. Depending on the conversion degree at the moment of quenching, this can lead to a net increase or decrease of CO2 conversion. In general, however, and certainly for equilibrium plasmas at high temperature, quenching after the plasma helps prevent recombination reactions and clearly enhances the final CO2 conversion. We also investigate the effect of different quenching cooling rates on the CO2 conversion and energy efficiency. Finally, we compare plasma-based conversion to purely thermal conversion. For warm plasmas with typical temperatures of 3000−4000 K, the conversion is roughly thermal. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000566481000003 | Publication Date | 2020-08-27 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1932-7447 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.7 | Times cited | Open Access | OpenAccess | |
Notes | Fonds Wetenschappelijk Onderzoek, G.0383.16N ; H2020 European Research Council, 810182 ; This research was supported by the FWO project (grant no. G.0383.16N) and the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (grant agreement no. 810182SCOPE ERC Synergy project). The calculations were performed using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen (UAntwerpen), a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI), and the UAntwerpen. | Approved | Most recent IF: 3.7; 2020 IF: 4.536 | ||
Call Number | PLASMANT @ plasmant @c:irua:172052 | Serial | 6407 | ||
Permanent link to this record |