Fast gas quenching of microwave plasma effluent for enhanced CO2 conversion

Hecimovic, A.; Kiefer, C.; Meindl, Arne; Antunes, R.; Fantz, U.

doi:10.1016/j.jcou.2023.102473

Cited by 16 publications

(14 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The basic concept of such a MW plasma torch is described in Leins et al, 23 and it has been studied for the conversion of CO 2 in various works, with and without obstructions in the effluent. 8,9,24,25 A water-cooled, 5 mm wide stainless steel nozzle was employed on top of the quartz tube for the following three reasons. First, the nozzle forces the mixing of the hot gas coming from the plasma (6000 K in the core) with the surrounding colder gas, enabling fast cooling rates and improved performances at quasi-atmospheric pressure.…”

Section: ■ Experimental Setup and Proceduresmentioning

confidence: 99%

“…Conversions of χ ≃ 52% and 30% were obtained with a microwave power of 2400 W for CO 2 inlet flows of 4670 and 9300 sccm, respectively, which correspond to CO outflows of 2450 and 2790 sccm. 9 Correspondingly, larger feed flows of O 2 would be generated and would need to be removed by membranes. In this scenario, assuming that 13 cm long membranes exposed to sufficiently high temperatures extract oxygen with a flux of 1.54 sccm cm −2 per membrane, more than 180 hollow fibers would be required.…”

Section: ■ Considerations For Upscalingmentioning

confidence: 99%

“…The MW plasma torch features four tangential gas inlets at the bottom, a coaxial (pin) and a cylindrical resonators, and a 84 mm long, flanged quartz tube with an inner diameter of 26 mm, inside which a plasma is ignited by coupling 2.45 GHz, magnetron-generated microwaves through a three-stub tuner (Muegge, magnetron head: MH3000S-213BB, power supply: ML3000D-111TC). The basic concept of such a MW plasma torch is described in Leins et al, and it has been studied for the conversion of CO 2 in various works, with and without obstructions in the effluent. ,,, …”

Section: Experimental Setup and Proceduresmentioning

confidence: 99%

“…2,3 Microwave (MW) and gliding arc plasmas have yielded the highest performances so far. 2,3 Among the strategies pursued to increase the efficiency of CO 2 splitting close to atmospheric pressure is the fast cooling of the converted gas to prevent backward reactions, e.g., CO + O + M → CO 2 + M. 4−6 This has been demonstrated either by employing water-cooled nozzles 7,8 or water-cooled channels 9 on top of the plasma generated by a MW plasma torch. The outlet gas mixture of plasma-based conversion technology consists typically of CO 2 , CO, and O 2 , which contrasts with the O 2 -free streams produced by electrolysis cells.…”

Section: ■ Introductionmentioning

confidence: 99%

“…Plasma technologies for conversion of carbon dioxide (CO 2 ) have attracted significant attention in the past decade, namely because of its compatibility with the intermittent operation of renewable energy sources . Numerous plasma sources and configurations have been studied and conversions beyond 50% have been reported. , Microwave (MW) and gliding arc plasmas have yielded the highest performances so far. , Among the strategies pursued to increase the efficiency of CO 2 splitting close to atmospheric pressure is the fast cooling of the converted gas to prevent backward reactions, e.g., CO + O + M → CO 2 + M. − This has been demonstrated either by employing water-cooled nozzles , or water-cooled channels on top of the plasma generated by a MW plasma torch. The outlet gas mixture of plasma-based conversion technology consists typically of CO 2 , CO, and O 2 , which contrasts with the O 2 -free streams produced by electrolysis cells .…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Proof of Concept for O₂ Removal with Multiple LCCF Membranes Accommodated in the Effluent of a CO₂ Plasma Torch

Antunes,

Wiegers,

Hecimovic

et al. 2023

ACS Sustainable Chem. Eng.

View full text Add to dashboard Cite

The removal of oxygen from the effluent of a CO 2 plasma using multiple perovskite La 0.6 Ca 0.4 Co 0.5 Fe 0.5 O 3−δ hollow fiber membranes is reported. A microwave plasma torch featuring a water-cooled 5 mm nozzle operated at quasi-atmospheric pressure was used. This configuration yielded moderate CO 2 conversions (≥20%) and sufficiently large temperatures to thermally activate up to 21 membranes distributed over various rows in the plasma effluent. The CO 2 conversion was only slightly affected by the microwave power and remained unchanged, regardless of the number of membranes placed in the effluent. The amount of permeated oxygen increased both with the microwave power and with the number of membranes, since the former yields hotter effluents (>700 °C) and the latter increases the surface area available for permeation. The largest O 2 permeation flow was obtained for 21 membranes and a microwave power of 2550 W: ≃42 sccm or ≃4.8% of the available O 2 . These correspond to the highest performances of such a plasma-membrane reactor thus far. The permeated O 2 flow was also affected by the argon flow purging the membranes. Using one membrane, the flow of extracted oxygen decreased for an Ar flow below 250 sccm, while the opposite was observed with 10 membranes, yielding an increase in the oxygen flow from ≃25 to ≃28 sccm upon decreasing the total Ar flow below 2500 sccm. Key aspects that must be tackled for the design and testing of a plasma-membrane prototype that aims to remove O 2 beyond 90% are discussed.

show abstract

Section: ■ Experimental Setup and Proceduresmentioning

confidence: 99%

Section: ■ Considerations For Upscalingmentioning

confidence: 99%

Section: Experimental Setup and Proceduresmentioning

confidence: 99%

Section: ■ Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Proof of Concept for O₂ Removal with Multiple LCCF Membranes Accommodated in the Effluent of a CO₂ Plasma Torch

Antunes,

Wiegers,

Hecimovic

et al. 2023

ACS Sustainable Chem. Eng.

View full text Add to dashboard Cite

show abstract

Temperature‐Dependent Kinetics of Plasma‐Based CO₂ Conversion: Interplay of Electron‐Driven and Thermal‐Driven Chemistry

Mohanan,

Snoeckx,

Cha

2024

ChemSusChem

View full text Add to dashboard Cite

The transformation of CO2 into chemical building blocks for various industries is considered a key technology in a net‐zero energy future. To realize this, plasma discharges are one of the most promising approaches thanks to their electron‐driven reactions and high operational flexibility. Most studies focused on room‐temperature and vibrationally‐excited discharges, however, lately, the importance of thermal reactions is considered. Therefore, we developed a temperature‐dependent plasma‐chemical reaction mechanism to investigate the temperature dependence of plasma‐based CO2 conversion. Here, we present the various effects of thermally‐driven reactions on the CO2 conversion as a function of the gas temperature and specific energy input. Our analysis pinpointed the key reactions controlling the plasma‐based CO2 conversion, shifting from an electron‐driven to a thermal‐driven regime. Additionally, we used the mechanism to verify the theoretical upper boundary of the process' energy efficiency, and discussed how our findings could lead to the further development and optimization of plasma discharges for efficient CO₂ conversion in the future.

show abstract

Advancing CO₂ to CO conversion: Detailed impact analysis of atmospheric molecules in an ultrashort pulse laser filament plasma reactor

Wang,

Deng,

Huang

et al. 2024

Micro & Optical Tech Letters

View full text Add to dashboard Cite

Capturing carbon dioxide (CO2) and transforming it into valuable fuels offers a dual benefit: the potential to reduce atmospheric CO2 levels and decrease our dependency on fossil fuels. Plasma‐assisted CO2 to carbon monoxide (CO) conversion stands out within the various CO2 recycling methods, with research primarily emphasizing its energy efficiency and conversion efficacy. However, investigations of CO2 conversion under real air conditions are relatively scarce, and the effects of the other atmospheric molecules on the CO2 conversion process require further exploration. We have induced plasma chemical reactions by generating ultrashort pulse laser filaments inside a sealed‐off cavity with variable air pressures. Simultaneously, we applied mid‐infrared laser absorption spectroscopy to monitor the time evolution of the reaction products. The peak CO2‐to‐CO conversion ratio was achieved at an air pressure of 8000 Pa, which resulted in a CO concentration of 82 ppm. The experimental results suggested that nitrogen (N2) plays a promoting role in CO2‐to‐CO conversion, while the presence of oxygen (O2) seems to hinder the process. The hydroxyl radical (OH) arising from water molecules (H2O) limits the accumulation of CO at lower air pressures. However, at higher air pressures, the reduced OH radical concentration shows negligible impact on the CO2‐to‐CO conversion ratios. In addition, the study revealed that atmospheric plasmas produce a high concentration of hydrogen cyanide (HCN), which is directly proportional to the levels of ambient humidity. This research contributes to the development of strategies to mitigate the production of harmful gases like HCN in CO2 conversion, thereby promoting the ecofriendly conversion of atmospheric CO2.

show abstract

Fast gas quenching of microwave plasma effluent for enhanced CO2 conversion

Cited by 16 publications

References 27 publications

Proof of Concept for O₂ Removal with Multiple LCCF Membranes Accommodated in the Effluent of a CO₂ Plasma Torch

Proof of Concept for O₂ Removal with Multiple LCCF Membranes Accommodated in the Effluent of a CO₂ Plasma Torch

Temperature‐Dependent Kinetics of Plasma‐Based CO₂ Conversion: Interplay of Electron‐Driven and Thermal‐Driven Chemistry

Advancing CO₂ to CO conversion: Detailed impact analysis of atmospheric molecules in an ultrashort pulse laser filament plasma reactor

Contact Info

Product

Resources

About

Fast gas quenching of microwave plasma effluent for enhanced CO2 conversion

Cited by 16 publications

References 27 publications

Proof of Concept for O2 Removal with Multiple LCCF Membranes Accommodated in the Effluent of a CO2 Plasma Torch

Proof of Concept for O2 Removal with Multiple LCCF Membranes Accommodated in the Effluent of a CO2 Plasma Torch

Temperature‐Dependent Kinetics of Plasma‐Based CO2 Conversion: Interplay of Electron‐Driven and Thermal‐Driven Chemistry

Advancing CO2 to CO conversion: Detailed impact analysis of atmospheric molecules in an ultrashort pulse laser filament plasma reactor

Contact Info

Product

Resources

About

Proof of Concept for O₂ Removal with Multiple LCCF Membranes Accommodated in the Effluent of a CO₂ Plasma Torch

Proof of Concept for O₂ Removal with Multiple LCCF Membranes Accommodated in the Effluent of a CO₂ Plasma Torch

Temperature‐Dependent Kinetics of Plasma‐Based CO₂ Conversion: Interplay of Electron‐Driven and Thermal‐Driven Chemistry

Advancing CO₂ to CO conversion: Detailed impact analysis of atmospheric molecules in an ultrashort pulse laser filament plasma reactor