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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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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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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 | Van Alphen, S.; Vermeiren, V.; Butterworth, T.; van den Bekerom, D.C.M.; van Rooij, G.J.; Bogaerts, A. | ||||
Title | Power Pulsing To Maximize Vibrational Excitation Efficiency in N2Microwave Plasma: A Combined Experimental and Computational Study | Type | A1 Journal article | ||
Year | 2020 | Publication | Journal Of Physical Chemistry C | Abbreviated Journal ![]() |
J Phys Chem C |
Volume | 124 | Issue | 3 | Pages | 1765-1779 |
Keywords | A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Plasma is gaining increasing interest for N2 fixation, being a flexible, electricity-driven alternative for the current conventional fossil fuel-based N2 fixation processes. As the vibrational-induced dissociation of N2 is found to be an energy-efficient pathway to acquire atomic N for the fixation processes, plasmas that are in vibrational nonequilibrium seem promising for this application. However, an important challenge in using nonequilibrium plasmas lies in preventing vibrational−translational (VT) relaxation processes, in which vibrational energy crucial for N2 dissociation is lost to gas heating. We present here both experimental and modeling results for the vibrational and gas temperature in a microsecond-pulsed microwave (MW) N2 plasma, showing how power pulsing can suppress this unfavorable VT relaxation and achieve a maximal vibrational nonequilibrium. By means of our kinetic model, we demonstrate that pulsed plasmas take advantage of the long time scale on which VT processes occur, yielding a very pronounced nonequilibrium over the whole N2 vibrational ladder. Additionally, the effect of pulse parameters like the pulse frequency and pulse width are investigated, demonstrating that the advantage of pulsing to inhibit VT relaxation diminishes for high pulse frequencies (around 7000 kHz) and long power pulses (above 400 μs). Nevertheless, all regimes studied here demonstrate a clear vibrational nonequilibrium while only requiring a limited power-on time, and thus, we may conclude that a pulsed plasma seems very interesting for energyefficient vibrational excitation. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000509438600001 | Publication Date | 2020-01-23 | |
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 | ||
Notes | Fonds Wetenschappelijk Onderzoek, 30505023 GoF9618n ; This research was supported by the Excellence of Science FWO-FNRS project (FWO Grant ID GoF9618n, EOS ID 30505023). 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:165586 | Serial | 5443 | ||
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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 | ||
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Author | Belov, I.; Vermeiren, V.; Paulussen, S.; Bogaerts, A. | ||||
Title | Carbon dioxide dissociation in a microwave plasma reactor operating in a wide pressure range and different gas inlet configurations | Type | A1 Journal article | ||
Year | 2018 | Publication | Journal of CO2 utilization | Abbreviated Journal ![]() |
J Co2 Util |
Volume | 24 | Issue | Pages | 386-397 | |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Microwave (MW) plasmas represent a promising solution for efficient CO2 dissociation. MW discharges are also very versatile and can be sustained at various pressure and gas flow regimes. To identify the most favorable conditions for the further scale-up of the CO2 decomposition reaction, a MW plasma reactor operating in pure CO2 in a wide pressure range (200 mbar–1 bar) is studied. Three different gas flow configurations are explored: a direct, reverse and a vortex regime. The CO2 conversion and energy efficiency drop almost linearly with increasing pressure, regardless of the gas flow regime. The results obtained in the direct flow configuration underline the importance of post-discharge cooling, as the exhaust of the MW plasma reactor in this regime expanded into the vacuum chamber without additional quenching. As a result, this system yields exhaust temperatures of up to 1000 K, which explains the lowest conversion (∼3.5% at 200 mbar and 2% at 1 bar). A post-discharge cooling step is introduced for the reverse gas inlet regime and allows the highest conversion to be achieved (∼38% at 200 mbar and 6.2% at 1 bar, with energy efficiencies of 23% and 3.7%). Finally, a tangential gas inlet is utilized in the vortex configuration to generate a swirl flow pattern. This results in the generation of a stable discharge in a broader range of CO2 flows (15–30 SLM) and the highest energy efficiencies obtained in this study (∼25% at 300 mbar and ∼13% at 1 bar, at conversions of 21% and 12%). The experimental results are complemented with computational fluid dynamics simulations and with the analysis of the latest literature to identify the further research directions. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000428234500045 | Publication Date | 2018-03-15 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2212-9820 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.292 | Times cited | 8 | Open Access | Not_Open_Access: Available from 16.03.2020 |
Notes | The research leading to these results has received funding from the European Union Seventh Framework Programme (FP7-PEOPLE-2013- ITN) under Grant Agreement№606889 (R | Approved | Most recent IF: 4.292 | ||
Call Number | PLASMANT @ plasmant @c:irua:150874 | Serial | 4955 | ||
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Author | Vermeiren, V. | ||||
Title | Chemical kinetics modeling of non-equilibrium and thermal effects in vibrationally active CO2 plasmas | Type | Doctoral thesis | ||
Year | 2020 | Publication | Abbreviated Journal ![]() |
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Volume | Issue | Pages | 207 p. | ||
Keywords | Doctoral thesis; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | Publication Date | |||
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ISSN | ISBN | Additional Links | UA library record | ||
Impact Factor | Times cited | Open Access | |||
Notes | Approved | Most recent IF: NA | |||
Call Number | UA @ admin @ c:irua:173385 | Serial | 6468 | ||
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