The Quest for Value‐Added Products from Carbon Dioxide and Water in a Dielectric Barrier Discharge: A Chemical Kinetics Study

Snoeckx, Ramses; Özkan, Alp; Reniers, François; Bogaerts, Annemie

doi:10.1002/cssc.201601234

Cited by 78 publications

(118 citation statements)

References 89 publications

(247 reference statements)

Supporting

Mentioning

105

Contrasting

Order By: Relevance

“…Indeed, recent modelling studies of CH 4 /O 2 mixtures have indicated a preferential formation of H 2 O from OH radicals [50]. These H 2 O molecules will promote the back reaction of CO into CO 2 , as suggested based on CO 2 /H 2 O models [56]. This can explain the lower CO 2 conversion in DRM for a BaTiO 3 packing, compared to pure CO 2 splitting.…”

Section: Discussionmentioning

confidence: 92%

Altering Conversion and Product Selectivity of Dry Reforming of Methane in a Dielectric Barrier Discharge by Changing the Dielectric Packing Material

et al. 2019

Self Cite

View full text Add to dashboard Cite

We studied the influence of dense, spherical packing materials, with different chemical compositions, on the dry reforming of methane (DRM) in a dielectric barrier discharge (DBD) reactor. Although not catalytically activated, a vast effect on the conversion and product selectivity could already be observed, an influence which is often neglected when catalytically activated plasma packing materials are being studied. The α-Al2O3 packing material of 2.0–2.24 mm size yields the highest total conversion (28%), as well as CO2 (23%) and CH4 (33%) conversion and a high product fraction towards CO (~70%) and ethane (~14%), together with an enhanced CO/H2 ratio of 9 in a 4.5 mm gap DBD at 60 W and 23 kHz. γ-Al2O3 is only slightly less active in total conversion (22%) but is even more selective in products formed than α-Al2O3. BaTiO3 produces substantially more oxygenated products than the other packing materials but is the least selective in product fractions and has a clear negative impact on CO2 conversion upon addition of CH4. Interestingly, when comparing to pure CO2 splitting and when evaluating differences in products formed, significantly different trends are obtained for the packing materials, indicating a complex impact of the presence of CH4 and the specific nature of the packing materials on the DRM process.

show abstract

Section: Discussionmentioning

confidence: 92%

Altering Conversion and Product Selectivity of Dry Reforming of Methane in a Dielectric Barrier Discharge by Changing the Dielectric Packing Material

et al. 2019

Self Cite

View full text Add to dashboard Cite

show abstract

“…Therefore, this reaction did not contributet oC O 2 conversion at 5% CH 4 in the mixture and waso nly importanta tl arger CH 4 fractions, as is clear from Figure 7. This reverse reactionw as also the limiting factor in CO 2 conversion in aD BD operating in a CO 2 /H 2 Om ixture, [90] and was even more important at higher H 2 Of ractionsi nt he mixture, which explainsw hy the addition of H 2 Or esulted in ad rop in the CO 2 conversion. [90] Thes itua-tion was ab it different in our case because at higherC H 4 fractions, the Ha toms formed upon dissociation of CH 4 played a more importantr ole in the CO 2 conversion, that is, the forward (loss) reactionu pon collision with Ha toms was more important than the reversereaction (production of CO 2 ).…”

Section: Calculated Species Densities Inside the Plasmamentioning

confidence: 93%

Dry Reforming of Methane in a Gliding Arc Plasmatron: Towards a Better Understanding of the Plasma Chemistry

et al. 2017

Self Cite

View full text Add to dashboard Cite

Dry reforming of methane (DRM) in a gliding arc plasmatron is studied for different CH fractions in the mixture. The CO and CH conversions reach their highest values of approximately 18 and 10 %, respectively, at 25 % CH in the gas mixture, corresponding to an overall energy cost of 10 kJ L (or 2.5 eV per molecule) and an energy efficiency of 66 %. CO and H are the major products, with the formation of smaller fractions of C H (x=2, 4, or 6) compounds and H O. A chemical kinetics model is used to investigate the underlying chemical processes. The calculated CO and CH conversion and the energy efficiency are in good agreement with the experimental data. The model calculations reveal that the reaction of CO (mainly at vibrationally excited levels) with H radicals is mainly responsible for the CO conversion, especially at higher CH fractions in the mixture, which explains why the CO conversion increases with increasing CH fraction. The main process responsible for CH conversion is the reaction with OH radicals. The excellent energy efficiency can be explained by the non-equilibrium character of the plasma, in which the electrons mainly activate the gas molecules, and by the important role of the vibrational kinetics of CO . The results demonstrate that a gliding arc plasmatron is very promising for DRM.

show abstract

“…In recent years, several plasma chemistry models were presented in literature, for CO 2 splitting, CH 4 reforming, CO 2 /CH 4 , CH 4 /O 2 , CO 2 /H 2 O, CO 2 /H 2 , as well as CO 2 /N 2 or CH 4 /N 2 mixtures, because N 2 is one of the most important components in gas effluents. Note, however, that not all these studies were devoted to gas conversion applications.…”

Section: Introductionmentioning

confidence: 99%

Plasma based CO₂ and CH₄ conversion: A modeling perspective

Bogaerts

Bie

Snoeckx

et al. 2016

Plasma Processes & Polymers

Self Cite

View full text Add to dashboard Cite

This paper gives an overview of our plasma chemistry modeling for CO 2 and CH 4 conversion in a dielectric barrier discharge (DBD) and microwave (MW) plasma. We focus on pure CO 2 splitting and pure CH 4 reforming, as well as mixtures of CO 2 /CH 4 , CH 4 /O 2 , and CO 2 /H 2 O. We show calculation results for the conversion, energy efficiency, and product formation, in comparison with experiments where possible. We also present the underlying chemical reaction pathways, to explain the observed trends. For pure CO 2 , a comparison is made between a DBD and MW plasma, illustrating that the higher energy efficiency of the latter is attributed to the more important role of the vibrational levels. K E Y W O R D S0D chemical kinetics model, CO 2 and CH 4 conversion, dielectric barrier discharges, microwave plasmas, plasma chemistry modeling | INTRODUCTIONIn recent years, there is increasing interest in plasma used for CO 2 and CH 4 conversion. Several types of plasma reactors are being investigated for this purpose, including (packed bed) dielectric barrier discharges (DBDs), [1][2][3][4][5][6][7][8][9][10][11][12][13][14] microwave (MW) plasmas, [15][16][17][18][19][20] ns-pulsed, [21] spark, [22][23][24] and gliding arc (GA) [25][26][27][28][29][30][31][32] discharges. Research focuses on pure CO 2 splitting into CO and O 2 , on CH 4 (and other hydrocarbons) reforming, and on mixtures of CO 2 with a hydrogen-source, that is, mainly CH 4 , but sometimes also H 2 O or H 2 , to produce value-added chemicals like syngas, hydrocarbons, and oxygenated products. Key performance indicators are the conversion and the energy efficiency of the process, as well as the possibility to produce specific value-added chemicals with good yields and selectivity. To realize the latter, the plasma should be combined with a catalyst (e.g., [3][4][5][6][7][8][9]33,34] ), as the plasma itself is a too reactive environment, and thus produces a wealth of reactive species, which easily recombine to form new molecules, without any selectivity.To improve the conversion, product yields and energy efficiency of this process, a good insight in the underlying plasma chemistry is crucial. This can be obtained by experiments, but measuring the reactive species densities inside the plasma is far from evident. Therefore, modeling of the plasma chemistry can be a valuable alternative, as it provides information on the most important chemical reaction pathways, and how to tune them to improve the conversion, energy efficiency, and product formation.In the 80s and 90s, some papers have been published on CO 2 plasma chemistry modeling, with applications to CO 2 lasers. [35][36][37] These models, however, did not consider the vibrational kinetics, which are important for energy efficient CO 2 conversion. [38] Some other papers have described the vibrational kinetics for gas flow applications, [39,40] but without focusing on the plasma chemistry. In 1981 Rusanov

show abstract

The Quest for Value‐Added Products from Carbon Dioxide and Water in a Dielectric Barrier Discharge: A Chemical Kinetics Study

Cited by 78 publications

References 89 publications

Altering Conversion and Product Selectivity of Dry Reforming of Methane in a Dielectric Barrier Discharge by Changing the Dielectric Packing Material

Altering Conversion and Product Selectivity of Dry Reforming of Methane in a Dielectric Barrier Discharge by Changing the Dielectric Packing Material

Dry Reforming of Methane in a Gliding Arc Plasmatron: Towards a Better Understanding of the Plasma Chemistry

Plasma based CO₂ and CH₄ conversion: A modeling perspective

Contact Info

Product

Resources

About

The Quest for Value‐Added Products from Carbon Dioxide and Water in a Dielectric Barrier Discharge: A Chemical Kinetics Study

Cited by 78 publications

References 89 publications

Altering Conversion and Product Selectivity of Dry Reforming of Methane in a Dielectric Barrier Discharge by Changing the Dielectric Packing Material

Altering Conversion and Product Selectivity of Dry Reforming of Methane in a Dielectric Barrier Discharge by Changing the Dielectric Packing Material

Dry Reforming of Methane in a Gliding Arc Plasmatron: Towards a Better Understanding of the Plasma Chemistry

Plasma based CO2 and CH4 conversion: A modeling perspective

Contact Info

Product

Resources

About

Plasma based CO₂ and CH₄ conversion: A modeling perspective