Records |
Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Kulkarni, S.; Gonzalez-Quiroga, A.; Nuñez, M.; Schuerewegen, C.; Perreault, P.; Goel, C.; Heynderickx, G.J.; Van Geem, K.M.; Marin, G.B. |
Title |
An experimental and numerical study of the suppression of jets, counterflow, and backflow in vortex units |
Type |
A1 Journal article |
Year |
2019 |
Publication |
AIChE journal |
Abbreviated Journal |
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Volume |
65 |
Issue |
8 |
Pages |
e16614-13 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
Vortex units are commonly considered for various single and multiphase applications due to their process intensification capabilities. The transition from gas‐only flow to gas–solid flow remains largely unexplored nonetheless. During this transition, primary flow phenomenon, jets, and secondary flow phenomena, counterflow and backflow, are substantially reduced, before a rotating solids bed is established. This transitional flow regime is referred to as the vortex suppression regime. In the present work, this flow transition is identified and validated through experimental and computational studies in two vortex units with a scale differing by a factor of 2, using spherical aluminum and alumina particles. This experimental data supports the proposed theoretical particle monolayer solids loading that allows estimation of vortex suppression regime solids capacity for any vortex unit. It is shown that the vortex suppression regime is established at a solids loading theoretically corresponding to a monolayer being formed in the unit for 1g‐Geldart D‐ and 1g‐Geldart B‐type particles. The model closely agrees with experimental vortex suppression range for both aluminum and alumina particles. The model, as well as the experimental data, shows that the flow suppression regime depends on unit dimensions, particle diameter, and particle density but is independent of gas flow rate. This combined study, based on experimental and computational data and on a theoretical model, reveals the vortex suppression to be one of the basic operational parameters to study flow in a vortex unit and that a simple monolayer model allows to estimate the needed solids loading for any vortex device to induce this flow transition. |
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Corporate Author |
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Thesis |
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Place of Publication |
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Editor |
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Language |
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Wos |
000474620800026 |
Publication Date |
2019-04-19 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0001-1541 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
no |
Call Number |
UA @ admin @ c:irua:162121 |
Serial |
7945 |
Permanent link to this record |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Meng, S.; Wu, L.; Liu, M.; Cui, Z.; Chen, Q.; Li, S.; Yan, J.; Wang, L.; Wang, X.; Qian, J.; Guo, H.; Niu, J.; Bogaerts, A.; Yi, Y. |
Title |
Plasma‐driven<scp>CO2</scp>hydrogenation to<scp>CH3OH</scp>over<scp>Fe2O3</scp>/<scp>γ‐Al2O3</scp>catalyst |
Type |
A1 Journal Article |
Year |
2023 |
Publication |
AIChE Journal |
Abbreviated Journal |
AIChE Journal |
Volume |
69 |
Issue |
10 |
Pages |
e18154 |
Keywords |
A1 Journal Article; chemisorbed oxygen, CO2 hydrogenation, iron-based catalyst, methanol production, plasma catalysis; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ; |
Abstract |
We report a plasma‐assisted CO<sub>2</sub>hydrogenation to CH<sub>3</sub>OH over Fe<sub>2</sub>O<sub>3</sub>/γ‐Al<sub>2</sub>O<sub>3</sub>catalysts, achieving 12% CO<sub>2</sub>conversion and 58% CH<sub>3</sub>OH selectivity at a temperature of nearly 80°C atm pressure. We investigated the effect of various supports and loadings of the Fe‐based catalysts, as well as optimized reaction conditions. We characterized catalysts by X‐ray powder diffraction (XRD), hydrogen temperature programmed reduction (H<sub>2</sub>‐TPR), CO<sub>2</sub>and CO temperature programmed desorption (CO<sub>2</sub>/CO‐TPD), high‐resolution transmission electron microscopy (HRTEM), scanning transmission electron microscopy (STEM), x‐ray photoelectron spectroscopy (XPS), Mössbauer, and Fourier transform infrared<bold>(</bold>FTIR). The XPS results show that the enhanced CO<sub>2</sub>conversion and CH<sub>3</sub>OH selectivity are attributed to the chemisorbed oxygen species on Fe<sub>2</sub>O<sub>3</sub>/γ‐Al<sub>2</sub>O<sub>3</sub>. Furthermore, the diffuse reflectance infrared Fourier transform spectroscopy (DRIFTs) and TPD results illustrate that the catalysts with stronger CO<sub>2</sub>adsorption capacity exhibit a higher reaction performance.<italic>In situ</italic>DRIFTS gain insight into the specific reaction pathways in the CO<sub>2</sub>/H<sub>2</sub>plasma. This study reveals the role of chemisorbed oxygen species as a key intermediate, and inspires to design highly efficient catalysts and expand the catalytic systems for CO<sub>2</sub>hydrogenation to CH<sub>3</sub>OH. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
001022420000001 |
Publication Date |
2023-07-07 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0001-1541 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.7 |
Times cited |
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Open Access |
Not_Open_Access |
Notes |
Fundamental Research Funds for the Central Universities, DUT18JC42 ; National Natural Science Foundation of China, 21908016 21978032 ; |
Approved |
Most recent IF: 3.7; 2023 IF: 2.836 |
Call Number |
PLASMANT @ plasmant @c:irua:197829 |
Serial |
8959 |
Permanent link to this record |