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Author | Blommaerts, N.; Hoeven, N.; Arenas Esteban, D.; Campos, R.; Mertens, M.; Borah, R.; Glisenti, A.; De Wael, K.; Bals, S.; Lenaerts, S.; Verbruggen, S.W.; Cool, P. | ||||
Title | Tuning the turnover frequency and selectivity of photocatalytic CO2 reduction to CO and methane using platinum and palladium nanoparticles on Ti-Beta zeolites | Type | A1 Journal article | ||
Year | 2021 | Publication | Chemical Engineering Journal | Abbreviated Journal | Chem Eng J |
Volume | 410 | Issue | Pages | 128234 | |
Keywords | A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL); Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) | ||||
Abstract | A Ti-Beta zeolite was used in gas phase photocatalytic CO2 reduction to reduce the charge recombination rate and increase the surface area compared to P25 as commercial benchmark, reaching 607 m2 g-1. By adding Pt nanoparticles, the selectivity can be tuned toward CO, reaching a value of 92% and a turnover frequency (TOF) of 96 µmol.gcat-1.h-1, nearly an order of magnitude higher in comparison with P25. By adding Pd nanoparticles the selectivity can be shifted from CO (70% for a bare Ti-Beta zeolite), toward CH4 as the prevalent species (60%). In this way, the selectivity toward CO or CH4 can be tuned by either using Pt or Pd. The TOF values obtained in this work outperform reported state-of-the-art values in similar research. The improved activity by adding the nanoparticles was attributed to an improved charge separation efficiency, together with a plasmonic contribution of the metal nanoparticles under the applied experimental conditions. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000623394200004 | Publication Date | 2021-01-09 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1385-8947 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 6.216 | Times cited | 15 | Open Access | OpenAccess |
Notes | N.B., S.L., S.W.V. and P.C. wish to thank the Flemish government and Catalisti for financial support and coordination in terms of a sprint SBO in the context of the moonshot project D2M. N.H. thanks the Flanders Innovation and Entrepreneurship (VLAIO) for the financial support. The Systemic Physiological and Ecotoxicological Research (SPHERE) group, R. Blust, University of Antwerp is acknowledged for the ICP-MS measurements. | Approved | Most recent IF: 6.216 | ||
Call Number | EMAT @ emat @c:irua:174591 | Serial | 6662 | ||
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Author | Girard-Sahun, F.; Biondo, O.; Trenchev, G.; van Rooij, G.; Bogaerts, A. | ||||
Title | Carbon bed post-plasma to enhance the CO2 conversion and remove O2 from the product stream | Type | A1 Journal article | ||
Year | 2022 | Publication | Chemical Engineering Journal | Abbreviated Journal | Chem Eng J |
Volume | 442 | Issue | Pages | 136268 | |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | CO2 conversion by plasma technology is gaining increasing interest. We present a carbon (charcoal) bed placed after a Gliding Arc Plasmatron (GAP) reactor, to enhance the CO2 conversion, promote O/O2 removal and in crease the CO fraction in the exhaust mixture. By means of an innovative (silo) system, the carbon is constantly supplied, to avoid carbon depletion upon reaction with O/O2. Using this carbon bed, the CO2 conversion is enhanced by almost a factor of two (from 7.6 to 12.6%), while the CO concentration even increases by a factor of three (from 7.2 to 21.9%), and O2 is completely removed from the exhaust mixture. Moreover, the energy ef ficiency of the conversion process drastically increases from 27.9 to 45.4%, and the energy cost significantly drops from 41.9 to 25.4 kJ.L− 1. We also present the temperature as a function of distance from the reactor outlet, as well as the CO2, CO and O2 concentrations and the temperature in the carbon bed as a function of time, which is important for understanding the underlying mechanisms. Indeed, these time-resolved measurements reveal that the initial enhancements in CO2 conversion and in CO concentration are not maintained in our current setup. Therefore, we present a model to study the gasification of carbon with different feed gases (i.e., O2, CO and CO2 separately), from which we can conclude that the oxygen coverage at the surface plays a key role in determining the product composition and the rate of carbon consumption. Indeed, our model insights indicate that the drop in CO2 conversion and in CO concentration after a few minutes is attributed to deactivation of the carbon bed, due to rapid formation of oxygen complexes at the surface. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000797716700002 | Publication Date | 0000-00-00 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1385-8947 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 15.1 | Times cited | Open Access | OpenAccess | |
Notes | Horizon 2020 Marie Skłodowska-Curie Actions; European Research Council; This research was supported by the European Research Council (ERC) under the European Union’s Horizon 2020 Research and Innovation programme (grant agreement No 810182 – SCOPE ERC Synergy project) and the European Union’s Horizon 2020 Research and Innovation programme under the Marie Sklodowska-Curie grant agreement No 813393 (PIONEER). The calculations were performed using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit | Approved | Most recent IF: 15.1 | ||
Call Number | PLASMANT @ plasmant @c:irua:188286 | Serial | 7052 | ||
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Author | Girard-Sahun, F.; Biondo, O.; Trenchev, G.; van Rooij, G.; Bogaerts, A. | ||||
Title | Carbon bed post-plasma to enhance the CO2 conversion and remove O2 from the product stream | Type | A1 Journal article | ||
Year | 2022 | Publication | Chemical Engineering Journal | Abbreviated Journal | Chem Eng J |
Volume | 442 | Issue | Pages | 136268 | |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | CO2 conversion by plasma technology is gaining increasing interest. We present a carbon (charcoal) bed placed after a Gliding Arc Plasmatron (GAP) reactor, to enhance the CO2 conversion, promote O/O2 removal and in crease the CO fraction in the exhaust mixture. By means of an innovative (silo) system, the carbon is constantly supplied, to avoid carbon depletion upon reaction with O/O2. Using this carbon bed, the CO2 conversion is enhanced by almost a factor of two (from 7.6 to 12.6%), while the CO concentration even increases by a factor of three (from 7.2 to 21.9%), and O2 is completely removed from the exhaust mixture. Moreover, the energy ef ficiency of the conversion process drastically increases from 27.9 to 45.4%, and the energy cost significantly drops from 41.9 to 25.4 kJ.L− 1. We also present the temperature as a function of distance from the reactor outlet, as well as the CO2, CO and O2 concentrations and the temperature in the carbon bed as a function of time, which is important for understanding the underlying mechanisms. Indeed, these time-resolved measurements reveal that the initial enhancements in CO2 conversion and in CO concentration are not maintained in our current setup. Therefore, we present a model to study the gasification of carbon with different feed gases (i.e., O2, CO and CO2 separately), from which we can conclude that the oxygen coverage at the surface plays a key role in determining the product composition and the rate of carbon consumption. Indeed, our model insights indicate that the drop in CO2 conversion and in CO concentration after a few minutes is attributed to deactivation of the carbon bed, due to rapid formation of oxygen complexes at the surface. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000797716700002 | Publication Date | 0000-00-00 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1385-8947 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 15.1 | Times cited | Open Access | OpenAccess | |
Notes | Horizon 2020 Marie Skłodowska-Curie Actions; European Research Council; This research was supported by the European Research Council (ERC) under the European Union’s Horizon 2020 Research and Innovation programme (grant agreement No 810182 – SCOPE ERC Synergy project) and the European Union’s Horizon 2020 Research and Innovation programme under the Marie Sklodowska-Curie grant agreement No 813393 (PIONEER). 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 thank R. De Meyer, K. Leyssens and S. Defossé for performing the charcoal characterizations. | Approved | Most recent IF: 15.1 | ||
Call Number | PLASMANT @ plasmant @c:irua:188286 | Serial | 7053 | ||
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Author | Van Alphen, S.; Ahmadi Eshtehardi, H.; O'Modhrain, C.; Bogaerts, J.; Van Poyer, H.; Creel, J.; Delplancke, M.-P.; Snyders, R.; Bogaerts, A. | ||||
Title | Effusion nozzle for energy-efficient NOx production in a rotating gliding arc plasma reactor | Type | A1 Journal article | ||
Year | 2022 | Publication | Chemical Engineering Journal | Abbreviated Journal | Chem Eng J |
Volume | 443 | Issue | Pages | 136529 | |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Plasma-based NOx production is of interest for sustainable N2 fixation, but more research is needed to improve its performance. One of the current limitations is recombination of NO back into N2 and O2 molecules immediately after the plasma reactor. Therefore, we developed a novel so-called “effusion nozzle”, to improve the performance of a rotating gliding arc plasma reactor for NOx production, but the same principle can also be applied to other plasma types. Experiments in a wide range of applied power, gas flow rates and N2/O2 ratios demonstrate an enhancement in NOx concentration by about 8%, and a reduction in energy cost by 22.5%. In absolute terms, we obtain NOx concentrations up to 5.9%, at an energy cost down to 2.1 MJ/mol, which are the best values reported to date in literature. In addition, we developed four complementary models to describe the gas flow, plasma temperature and plasma chemistry, aiming to reveal why the effusion nozzle yields better performance. Our simulations reveal that the effusion nozzle acts as very efficient heat sink, causing a fast drop in gas temperature when the gas molecules leave the plasma, hence limiting the recombination of NO back into N2 and O2. This yields an overall higher NOx concentration than without the effusion nozzle. This immediate quenching right at the end of the plasma makes our effusion nozzle superior to more conventional cooling options, like water cooling In addition, this higher NOx concentration can be obtained at a slightly lower power, because the effusion nozzle allows for the ignition and sustainment of the plasma at somewhat lower power. Hence, this also explains the lower energy cost. Overall, our experimental results and detailed modeling analysis will be useful to improve plasma-based NOx production in other plasma reactors as well. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000800010600003 | Publication Date | 0000-00-00 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1385-8947 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 15.1 | Times cited | Open Access | OpenAccess | |
Notes | This research was supported by the Excellence of Science FWO-FNRS project (FWO grant ID GoF9618n, EOS ID 30505023), the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement No 810182 – SCOPE ERC Synergy project), and through long-term structural funding (Methusalem). 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: 15.1 | ||
Call Number | PLASMANT @ plasmant @c:irua:188283 | Serial | 7057 | ||
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Author | Lang, X.; Ouyang, Y.; Vandewalle, L.A.; Goshayeshi, B.; Chen, S.; Madanikashani, S.; Perreault, P.; Van Geem, K.M.; van Geem, K.M. | ||||
Title | Gas-solid hydrodynamics in a stator-rotor vortex chamber reactor | Type | A1 Journal article | ||
Year | 2022 | Publication | Chemical engineering journal | Abbreviated Journal | Chem Eng J |
Volume | 446 | Issue | 5 | Pages | 137323-12 |
Keywords | A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) | ||||
Abstract | The gas-solid vortex reactor (GSVR) has enormous process intensification potential. However the huge gas consumption can be a serious disadvantage for the GSVR in some applications such as fast pyrolysis. In this work, we demonstrate a recent novel design, where a stator-rotor vortex chamber (STARVOC) is driven by the fluid's kinetic energy, to decouple the solids bed rotation and gas. Gas-solid fluidization by using air and monosized aluminum balls was performed to investigate the hydrodynamics. A constructed fluidization flow regime map for a fixed solids loading of 100 g shows that the bed can only be fluidized for a rotation speed between 200 and 400 RPM. Below 200 RPM, particles settle down on the bottom plate and cannot form a stable bed due to inertia and friction. Above 400 RPM, the bed cannot be fluidized with superficial velocities up to 1.8 m/s (air flow rate of 90 Nm(3)/h). The bed thickness shows some non-uniformities, being smaller at the top of the bed than at the bottom counterpart. However by increasing the air flow rate or rotation speed the axial nonuniformity can be resolved. The bed pressure drop first increases with increasing gas flow rate and then levels off, showing similar characteristics as conventional fluidized beds. Theoretical pressure drops calculated from mathematical models such as Kao et al. model agree well with experimental measurements. Particle velocity discrepancies between the top and bottom particles reveal that the impact of gravity cannot be completely neglected. Design guidelines and possible applications for further development of STARVOC concept are proposed based on fundamental data provided in this work. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000833418100006 | Publication Date | 2022-06-01 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1385-8947; 1873-3212 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 15.1 | Times cited | Open Access | OpenAccess | |
Notes | Approved | Most recent IF: 15.1 | |||
Call Number | UA @ admin @ c:irua:189283 | Serial | 7167 | ||
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Author | Wang, Y.; Chen, Y.; Harding, J.; He, H.; Bogaerts, A.; Tu, X. | ||||
Title | Catalyst-free single-step plasma reforming of CH4 and CO2 to higher value oxygenates under ambient conditions | Type | A1 Journal article | ||
Year | 2022 | Publication | Chemical Engineering Journal | Abbreviated Journal | Chem Eng J |
Volume | 450 | Issue | Pages | 137860 | |
Keywords | A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Direct conversion of CH4 and CO2 to liquid fuels and chemicals under mild conditions is appealing for biogas conversion and utilization but challenging due to the inert nature of both gases. Herein, we report a promising plasma process for the catalyst-free single-step conversion of CH4 and CO2 into higher value oxygenates (i.e., methanol, acetic acid, ethanol, and acetone) at ambient pressure and room temperature using a water-cooled dielectric barrier discharge (DBD) reactor, with methanol being the main liquid product. The distribution of liquid products could be tailored by tuning the discharge power, reaction temperature and residence time. Lower discharge powers (10–15 W) and reaction temperatures (5–20 ◦ C) were favourable for the production of liquid products, achieving the highest methanol selectivity of 43% at 5 ◦ C and 15 W. A higher discharge power and reaction temperature, on the other hand, produced more gaseous products, particularly H2 (up to 26% selectivity) and CO (up to 33% selectivity). In addition, varying these process parameters (discharge power, reaction temperature and residence time) resulted in a simultaneous change in key discharge properties, such as mean electron energy (Ee), electron density (ne) and specific energy input (SEI), all of which are essential determiners of plasma chemical reactions. According to the results of artificial neural network (ANN) models, the relative importance of these process parameters and key discharge indicators on reaction performance follows the order: discharge power > reaction temperature > residence time, and SEI > ne > Ee, respectively. This work provides new insights into the contributions and tuning mechanism of multiple parameters for optimizing the reaction performance (e.g., liquid production) in the plasma gas conversion process. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000830813300004 | Publication Date | 0000-00-00 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1385-8947 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 15.1 | Times cited | Open Access | OpenAccess | |
Notes | This project received funding from the European Union’s Horizon 2020 research and innovation program under the Marie SklodowskaCurie grant agreement No. 813393. | Approved | Most recent IF: 15.1 | ||
Call Number | PLASMANT @ plasmant @c:irua:189502 | Serial | 7100 | ||
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Author | Brienza, F.; Van Aelst, K.; Devred, F.; Magnin, D.; Tschulkow, M.; Nimmegeers, P.; Van Passel, S.; Sels, B.F.; Gerin, P.; Debecker, D.P.; Cybulska, I. | ||||
Title | Unleashing lignin potential through the dithionite-assisted organosolv fractionation of lignocellulosic biomass | Type | A1 Journal article | ||
Year | 2022 | Publication | Chemical Engineering Journal | Abbreviated Journal | Chem Eng J |
Volume | 450 | Issue | 3 | Pages | 138179-14 |
Keywords | A1 Journal article; Engineering sciences. Technology; Engineering Management (ENM); Intelligence in PRocesses, Advanced Catalysts and Solvents (iPRACS) | ||||
Abstract | The development of biomass pretreatment approaches that, next to (hemi)cellulose valorization, aim at the conversion of lignin to chemicals is essential for the long-term success of a biorefinery. Herein, we discuss a dithionite-assisted organosolv fractionation (DAOF) of lignocellulose in n-butanol and water to produce cellulosic pulp and mono-/oligo-aromatics. The study frames the technicalities of this biorefinery process and relates them to the features of the obtained product streams. We comprehensively identify and quantify all products of interest: solid pulp (acid hydrolysis-HPLC, ATR-FTIR, XRD, SEM, enzymatic hydrolysis-HPLC), lignin derivatives (GPC, GC-MS/FID, 1H-13C HSQC NMR, ICP-AES), and carbohydrate derivatives (HPLC). These results were used for inspecting the economic feasibility of DAOF. In the best process configuration, a high yield of monophenolics was reached (~20%, based on acid insoluble lignin in birch sawdust). Various other lignocellulosic feedstocks were also explored, showing that DAOF is particularly effective on hardwood and herbaceous biomass. Overall, this study demonstrates that DAOF is a viable fractionation method for the sustainable upgrading of lignocellulosic biomass. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000888204900005 | Publication Date | 2022-07-20 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1385-8947; 1873-3212 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 15.1 | Times cited | Open Access | OpenAccess | |
Notes | Approved | Most recent IF: 15.1 | |||
Call Number | UA @ admin @ c:irua:189322 | Serial | 7373 | ||
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Author | Orozco-Jimenez, A.J.; Pinilla-Fernandez, D.A.; Pugliese, V.; Bula, A.; Perreault, P.; Gonzalez-Quiroga, A. | ||||
Title | Angular momentum based-analysis of gas-solid fluidized beds in vortex chambers | Type | A1 Journal article | ||
Year | 2023 | Publication | Chemical engineering journal | Abbreviated Journal | |
Volume | 457 | Issue | Pages | 141222-21 | |
Keywords | A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) | ||||
Abstract | Gas-solid vortex chambers are a promising alternative for reactive and non-reactive processes requiring enhanced heat and mass transfer rates and order-of-milliseconds contact time. The conservation of angular momentum is instrumental in understanding how the interactions between gas, particulate solids, and chamber walls influence the formation of a rotating solids bed. Therefore, this work applies the conservation of angular momentum to derive a model that gives the average angular velocity of solids in terms of gas injection velocity, wall-solids bed drag coefficient, gas and particle properties, and chamber geometry. Three datasets from published studies, comprising 1 g-Geldart B- and d-type particles in different vortex chambers, validate the model results. Using a sensitivity analysis, we assessed the effect of input variables on the average angular velocity of solids, average void fraction, and average bed height. Results indicate that the top and bottom end-wall boundaries exert the most significant braking effect on the rotating solids bed compared with the cylindrical outer wall and gas injection boundaries. The wall-solids bed drag coefficient appears independent of the gas injection velocity for a wide range of operating conditions. The proposed model is a valuable tool for analyzing and comparing gas–solid vortex typologies, unraveling improvement opportunities, and scale-up. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000951011600001 | Publication Date | 2022-12-29 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1385-8947; 1873-3212 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 15.1 | Times cited | Open Access | OpenAccess | |
Notes | Approved | Most recent IF: 15.1; 2023 IF: 6.216 | |||
Call Number | UA @ admin @ c:irua:192868 | Serial | 7282 | ||
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Author | Andersen, Ja.; Holm, Mc.; van 't Veer, K.; Christensen, Jm.; Østberg, M.; Bogaerts, A.; Jensen, Ad. | ||||
Title | Plasma-catalytic ammonia synthesis in a dielectric barrier discharge reactor: A combined experimental study and kinetic modeling | Type | A1 Journal article | ||
Year | 2023 | Publication | Chemical engineering journal | Abbreviated Journal | |
Volume | 457 | Issue | Pages | 141294 | |
Keywords | A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Plasma-catalytic ammonia synthesis in a dielectric barrier discharge reactor has emerged as a possible route for electrification of nitrogen fixation. In this study, we use a combination of experiments and a plasma kinetic model to investigate the ammonia synthesis from N2 and H2, both with and without a solid packing material in the plasma zone. The effect of plasma power, feed flow rate, N2:H2 feed ratio, gas residence time, temperature, and packing material (MgAl2O4 alone or impregnated with Co or Ru) on the ammonia synthesis rate were examined in the experiments. The kinetic model was employed to improve our understanding of the ammonia formation pathways and identify possible changes in these pathways when altering the N2:H2 feed ratio. A higher NH3 synthesis rate was achieved when increasing the feed flow rate, as well as when increasing the gas tem-perature from 100 to 200 ◦C when a packing material was present in the plasma. At the elevated temperature of 200 ◦C, an optimum in the NH3 synthesis rate was observed at an equimolar feed ratio (N2:H2 =1:1) for the plasma alone and MgAl2O4, while a N2-rich feed was favored for Ru/MgAl2O4 and Co/MgAl2O4. The optimum in the synthesis rate with the N2-rich feed, where high energy electrons are more likely to collide with N2, suggests that the rate-limiting step is the dissociation of N2 in the gas phase. This is supported by the kinetic model when packing material was used. However, for the plasma alone, the model found that the N2 dissociation is only rate limiting in H2-rich feeds, whereas the limited access to H in N2-rich feeds makes the hydrogenation of N species limiting. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 001058978000001 | Publication Date | 2023-01-05 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1385-8947 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 15.1 | Times cited | Open Access | OpenAccess | |
Notes | We thank Topsoe A/S for providing the catalytic materials used in the study, the research group PLASMANT (University of Antwerp) for sharing their plasma kinetic model and allocating time on their cluster for the calculations, and the Department of Chemical and Biochemical Engineering (Technical University of Denmark) for funding the project. | Approved | Most recent IF: 15.1; 2023 IF: 6.216 | ||
Call Number | PLASMANT @ plasmant @c:irua:195877 | Serial | 7234 | ||
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Author | Van Alphen, S.; Hecimovic, A.; Kiefer, C.K.; Fantz, U.; Snyders, R.; Bogaerts, A. | ||||
Title | Modelling post-plasma quenching nozzles for improving the performance of CO2 microwave plasmas | Type | A1 Journal article | ||
Year | 2023 | Publication | Chemical engineering journal | Abbreviated Journal | |
Volume | 462 | Issue | Pages | 142217 | |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Given the ecological problems associated to the CO2 emissions of fossil fuels, plasma technology has gained interest for conversion of CO2 into value-added products. Microwave plasmas operating at atmospheric pressure have proven to be especially interesting, due to the high gas temperatures inside the reactor (i.e. up to 6000 K) allowing for efficient thermal dissociation of CO2 into CO and O2. However, the performance of these high temperature plasmas is limited by recombination of CO back into CO2 once the gas cools down in the afterglow. In this work, we computationally investigated several quenching nozzles, developed and experimentally tested by Hecimovic et al., [1] for their ability to quickly cool the gas after the plasma, thereby quenching the CO recombination reactions. Using a 3D computational fluid dynamics model and a quasi-1D chemical kinetics model, we reveal that a reactor without nozzle lacks gas mixing between hot gas in the center and cold gas near the reactor walls. Especially at low flow rates, where there is an inherent lack of convective cooling due to the low gas flow velocity, the temperature in the afterglow remains high (between 2000 and 3000 K) for a relatively long time (in the 0.1 s range). As shown by our quasi-1D chemical kinetics model, this results in a important loss of CO due to recombination reactions. Attaching a nozzle in the effluent of the reactor induces fast gas quenching right after the plasma. Indeed, it introduces (i) more convective cooling by forcing cool gas near the walls to mix with hot gas in the center of the reactor, as well as (ii) more conductive cooling through the water-cooled walls of the nozzle. Our model shows that gas quenching and the suppression of recombination reactions have more impact at low flow rates, where recombination is the most limiting factor in the conversion process. |
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000962382600001 | Publication Date | 2023-03-03 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1385-8947 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 15.1 | Times cited | Open Access | OpenAccess | |
Notes | This research was supported by the Excellence of Science FWO-FNRS project (FWO grant ID GoF9618n, EOS ID 30505023), the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement No 810182 – SCOPE ERC Synergy project), and through long-term structural funding (Methusalem). 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: 15.1; 2023 IF: 6.216 | ||
Call Number | PLASMANT @ plasmant @c:irua:195889 | Serial | 7250 | ||
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Author | Van Alphen, S.; Hecimovic, A.; Kiefer, C.K.; Fantz, U.; Snyders, R.; Bogaerts, A. | ||||
Title | Modelling post-plasma quenching nozzles for improving the performance of CO2 microwave plasmas | Type | A1 Journal article | ||
Year | 2023 | Publication | Chemical engineering journal | Abbreviated Journal | |
Volume | 462 | Issue | Pages | 142217 | |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Given the ecological problems associated to the CO2 emissions of fossil fuels, plasma technology has gained interest for conversion of CO2 into value-added products. Microwave plasmas operating at atmospheric pressure have proven to be especially interesting, due to the high gas temperatures inside the reactor (i.e. up to 6000 K) allowing for efficient thermal dissociation of CO2 into CO and O2. However, the performance of these high temperature plasmas is limited by recombination of CO back into CO2 once the gas cools down in the afterglow. In this work, we computationally investigated several quenching nozzles, developed and experimentally tested by Hecimovic et al., [1] for their ability to quickly cool the gas after the plasma, thereby quenching the CO recombination reactions. Using a 3D computational fluid dynamics model and a quasi-1D chemical kinetics model, we reveal that a reactor without nozzle lacks gas mixing between hot gas in the center and cold gas near the reactor walls. Especially at low flow rates, where there is an inherent lack of convective cooling due to the low gas flow velocity, the temperature in the afterglow remains high (between 2000 and 3000 K) for a relatively long time (in the 0.1 s range). As shown by our quasi-1D chemical kinetics model, this results in a important loss of CO due to recombination reactions. Attaching a nozzle in the effluent of the reactor induces fast gas quenching right after the plasma. Indeed, it introduces (i) more convective cooling by forcing cool gas near the walls to mix with hot gas in the center of the reactor, as well as (ii) more conductive cooling through the water-cooled walls of the nozzle. Our model shows that gas quenching and the suppression of recombination reactions have more impact at low flow rates, where recombination is the most limiting factor in the conversion process. |
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Language | Wos | 000962382600001 | Publication Date | 2023-03-03 | |
Series Editor | Series Title | Abbreviated Series Title | |||
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ISSN | 1385-8947 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 15.1 | Times cited | Open Access | OpenAccess | |
Notes | This research was supported by the Excellence of Science FWO-FNRS project (FWO grant ID GoF9618n, EOS ID 30505023), the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement No 810182 – SCOPE ERC Synergy project), and through long-term structural funding (Methusalem). 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: 15.1; 2023 IF: 6.216 | ||
Call Number | PLASMANT @ plasmant @c:irua:195889 | Serial | 7259 | ||
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Author | Morais, E.; Delikonstantis, E.; Scapinello, M.; Smith, G.; Stefanidis, G.D.; Bogaerts, A. | ||||
Title | Methane coupling in nanosecond pulsed plasmas: Correlation between temperature and pressure and effects on product selectivity | Type | A1 Journal article | ||
Year | 2023 | Publication | Chemical engineering journal | Abbreviated Journal | |
Volume | 462 | Issue | Pages | 142227 | |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | We present a zero-dimensional kinetic model to characterise specifically the gas-phase dynamics of methane conversion in a nanosecond pulsed discharge (NPD) plasma reactor. The model includes a systematic approach to capture the nanoscale power discharges and the rapid ensuing changes in electric field, gas and electron temperature, as well as species densities. The effects of gas temperature and reactor pressure on gas conversion and product selectivity are extensively investigated and validated against experimental work. We discuss the important reaction pathways and provide an analysis of the dynamics of the heating and cooling mechanisms. H radicals are found to be the most populous plasma species and they participate in hydrogenation and dehydrogenation reactions, which are the dominant recombination reactions leading to C2H4 and C2H2 as main products (depending on the pressure). |
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Language | Wos | 000983631500001 | Publication Date | 2023-03-02 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1385-8947 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 15.1 | Times cited | Open Access | OpenAccess | |
Notes | We gratefully acknowledge financial support by the Flemish Government through the Moonshot cSBO project “Power-to-Olefins” (P2O; HBC.2020.2620). | Approved | Most recent IF: 15.1; 2023 IF: 6.216 | ||
Call Number | PLASMANT @ plasmant @c:irua:195881 | Serial | 7246 | ||
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Author | Liu, R.; Hao, Y.; Wang, T.; Wang, L.; Bogaerts, A.; Guo, H.; Yi, Y. | ||||
Title | Hybrid plasma-thermal system for methane conversion to ethylene and hydrogen | Type | A1 Journal article | ||
Year | 2023 | Publication | Chemical engineering journal | Abbreviated Journal | |
Volume | 463 | Issue | Pages | 142442 | |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | By combining dielectric barrier discharge plasma and external heating, we exploit a two-stage hybrid plasmathermal system (HPTS), i.e., a plasma stage followed by a thermal stage, for direct non-oxidative coupling of CH4 to C2H4 and H2, yielding a CH4 conversion of ca. 17 %. In the two-stage HPTS, the plasma first converts CH4 into C2H6 and C3H8, which in the thermal stage leads to a high C2H4 selectivity of ca. 63 % by pyrolysis, with H2 selectivity of ca. 64 %. |
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Language | Wos | 000953890500001 | Publication Date | 2023-03-16 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1385-8947 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 15.1 | Times cited | Open Access | OpenAccess | |
Notes | This work was supported by the National Natural Science Foundation of China [22272015, 21503032], the Fundamental Research Funds for the Central Universities of China [DUT21JC40]. | Approved | Most recent IF: 15.1; 2023 IF: 6.216 | ||
Call Number | PLASMANT @ plasmant @c:irua:195888 | Serial | 7253 | ||
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Author | Wang, J.; Zhang, K.; Bogaerts, A.; Meynen, V. | ||||
Title | 3D porous catalysts for plasma-catalytic dry reforming of methane : how does the pore size affect the plasma-catalytic performance? | Type | A1 Journal article | ||
Year | 2023 | Publication | Chemical engineering journal | Abbreviated Journal | |
Volume | 464 | Issue | Pages | 142574-12 | |
Keywords | A1 Journal article; Laboratory of adsorption and catalysis (LADCA); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | The effect of pore size on plasma catalysis is crucial but still unclear. Studies have shown plasma cannot enter micropores and mesopores, so catalysts for traditional thermocatalysis may not fit plasma catalysis. Here, 3D porous Cu and CuO with different pore sizes were prepared using uniform silica particles (10–2000 nm) as templates, and compared in plasma-catalytic dry reforming. In most cases, the smaller the pore size, the higher the conversion of CH4 and CO2. Large pores reachable by more electrons did not improve the reaction efficiency. We attribute this to the small surface area and large crystallite size, as indicated by N2-sorption, mercury intrusion and XRD. While the smaller pores might not be reachable by electrons, due to the sheath formed in front of them, as predicted by modeling, they can still be reached by radicals formed in the plasma, and ions can even be attracted into these pores. An exception are the samples synthesized from 1 μm silica, which show better performance. We believe this is due to the electric field enhancement for pore sizes close to the Debye length. The performances of CuO and Cu with different pore sizes can provide references for future research on oxide supports and metal components of plasma catalysts. | ||||
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Language | Wos | 000966076400001 | Publication Date | 2023-03-21 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1385-8947; 1873-3212 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 15.1 | Times cited | Open Access | OpenAccess | |
Notes | Approved | Most recent IF: 15.1; 2023 IF: 6.216 | |||
Call Number | UA @ admin @ c:irua:194862 | Serial | 7262 | ||
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Author | Wang, J.; Zhang, K.; Meynen, V.; Bogaerts, A. | ||||
Title | Dry reforming in a dielectric barrier discharge reactor with non-uniform discharge gap : effects of metal rings on the discharge behavior and performance | Type | A1 Journal article | ||
Year | 2023 | Publication | Chemical engineering journal | Abbreviated Journal | |
Volume | Issue | Pages | 142953-29 | ||
Keywords | A1 Journal article; Laboratory of adsorption and catalysis (LADCA); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | The application of dielectric barrier discharge (DBD) plasma reactors is promising in various environmental and energy processes, but is limited by their low energy yield. In this study, we put a number of stainless steel rings over the inner electrode rod of the DBD reactor to change the local discharge gap and electric field, and we studied the dry reforming performance. At 50 W supplied power, the metal rings mostly have a negative impact on the performance, which we attribute to the non-uniform spatial distribution of the discharges caused by the rings. However, at 30 W supplied power, the energy yield is higher than at 50 W and the placement of the rings improves the performance of the reactor. More rings and with a larger cross-sectional diameter can further improve the performance. The reactor with 20 rings with a 3.2 mm cross-sectional diameter exhibits the best performance in this study. Compared to the reactor without rings, it increases the CO2 conversion from 7% to 16 %, the CH4 conversion from 12% to 23%, and the energy yield from 0.05 mmol/kJ supplied power to 0.1 mmol/kJ (0.19 mmol/kJ if calculated from the plasma power), respectively. The presence of the rings increases the local electric field, the displaced charge and the discharge fraction, and also makes the discharge more stable and with more uniform intensity. It also slightly improves the selectivity to syngas. The performance improvement observed by placing stainless steel rings in this study may also be applicable to other plasma-based processes. | ||||
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Language | Wos | 000986051300001 | Publication Date | 2023-04-17 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1385-8947; 1873-3212 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 15.1 | Times cited | Open Access | OpenAccess | |
Notes | Approved | Most recent IF: 15.1; 2023 IF: 6.216 | |||
Call Number | UA @ admin @ c:irua:195603 | Serial | 7264 | ||
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Author | Ag, K.R.; Minja, A.C.; Ninakanti, R.; Van Hal, M.; Dingenen, F.; Borah, R.; Verbruggen, S.W. | ||||
Title | Impact of soot deposits on waste gas-to-electricity conversion in a TiO₂/WO₃-based photofuel cell | Type | A1 Journal article | ||
Year | 2023 | Publication | Chemical engineering journal | Abbreviated Journal | |
Volume | 470 | Issue | Pages | 144390-13 | |
Keywords | A1 Journal article; Engineering sciences. Technology | ||||
Abstract | An unbiased photo-fuel cell (PFC) is a device that integrates the functions of a photoanode and a cathode to achieve simultaneous light-driven oxidation and dark reduction reactions. As such, it generates electricity while degrading pollutants like volatile organic compounds (VOCs). The photoanode is excited by light to generate electron-hole pairs, which give rise to a photocurrent, and are utilized to oxidise organic pollutants simultaneously. Here we have systematically studied various TiO2/WO3 photoanodes towards their photocatalytic soot degradation performance, PFC performance in the presence of VOCs, and the combination of both. The latter thus mimics an urban environment where VOCs and soot are present simultaneously. The formation of a type-II heterojunction after the addition of a thin TiO2 top layer over a dense WO3 bottom layer, improved both soot oxidation efficiency as well as photocurrent generation, thus paving the way towards low-cost PFC technology for energy recovery from real polluted air. | ||||
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Language | Wos | 001030456200001 | Publication Date | 2023-06-25 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1385-8947; 1873-3212 | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor | 15.1 | Times cited | Open Access | Not_Open_Access: Available from 29.12.2023 | |
Notes | Approved | Most recent IF: 15.1; 2023 IF: 6.216 | |||
Call Number | UA @ admin @ c:irua:197222 | Serial | 8882 | ||
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Author | Zhang, K.; Wang, J.; Ninakanti, R.; Verbruggen, S.W. | ||||
Title | Solvothermal synthesis of mesoporous TiO2 with tunable surface area, crystal size and surface hydroxylation for efficient photocatalytic acetaldehyde degradation | Type | A1 Journal article | ||
Year | 2023 | Publication | Chemical engineering journal | Abbreviated Journal | |
Volume | 474 | Issue | Pages | 145188-14 | |
Keywords | A1 Journal article; Engineering sciences. Technology; Laboratory of adsorption and catalysis (LADCA) | ||||
Abstract | Photocatalytic acetaldehyde degradation exhibits satisfactory performance only at relatively low acetaldehyde flow rates, predominately below 10 × 10-3 mL/min, leaving ample room for improvement. Therefore, it is necessary to prepare more efficient photocatalysts for acetaldehyde degradation. Moreover, the impact of the interaction strength between the titania surface and surface water on the photocatalytic acetaldehyde efficiency is poorly understood. To address these issues, in this work a series of (0 0 1)-faceted anatase titania samples with various surface properties and structures were synthesized via a solvothermal method and tested at high acetaldehyde flow rates under UV light irradiation. With increasing solvothermal time, the pore volume, surface area, and the abundance of surface OH groups all increased, while the crystallite size decreased. These were all identified to be beneficial to promote the degradation performance. When the solvothermal temperature was 180 ℃ and the reaction time was 5 h, the prepared sample displayed the most efficient performance at 19.25× 10-3 mL/min of acetaldehyde (conversion of (74 ± 1)% versus (29 ± 1)% for P25), and achieved a 100 % conversion at 16 × 10-3 mL/min. A weaker interaction strength between surface water and the titania surface was found to improve the acetaldehyde adsorption capacity, thereby promoting the acetaldehyde degradation efficiency. The stability of the best performing sample was tested over 48 h, demonstrating a highly stable performance with no signs of deactivation. Even at a relative humidity of 30 %, the acetaldehyde conversion retains 82% of its efficiency in a dry atmosphere, highlighting its potential in practical applications. | ||||
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Language | Wos | 001144928800001 | Publication Date | 2023-08-05 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1385-8947; 1873-3212 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 15.1 | Times cited | Open Access | Not_Open_Access: Available from 06.02.2024 | |
Notes | Approved | Most recent IF: 15.1; 2023 IF: 6.216 | |||
Call Number | UA @ admin @ c:irua:198652 | Serial | 8933 | ||
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Author | Wang, K.; Ceulemans, S.; Zhang, H.; Tsonev, I.; Zhang, Y.; Long, Y.; Fang, M.; Li, X.; Yan, J.; Bogaerts, A. | ||||
Title | Inhibiting recombination to improve the performance of plasma-based CO2 conversion | Type | A1 Journal Article | ||
Year | 2024 | Publication | Chemical Engineering Journal | Abbreviated Journal | Chemical Engineering Journal |
Volume | 481 | Issue | Pages | 148684 | |
Keywords | A1 Journal Article; Plasma-based CO2 splitting Recombination reactions In-situ gas sampling Fluid dynamics modeling Kinetics modeling Afterglow quenching; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ; | ||||
Abstract | Warm plasma offers a promising route for CO2 splitting into valuable CO, yet recombination reactions of CO with oxygen, forming again CO2, have recently emerged as critical limitation. This study combines experiments and fluid dynamics + chemical kinetics modelling to comprehensively analyse the recombination reactions upon CO2 splitting in an atmospheric plasmatron. We introduce an innovative in-situ gas sampling technique, enabling 2D spatial mapping of gas product compositions and temperatures, experimentally confirming for the first time the substantial limiting effect of CO recombination reactions in the afterglow region. Our results show that the CO mole fraction at a 5 L/min flow rate drops significantly from 11.9 % at a vertical distance of z = 20 mm in the afterglow region to 8.6 % at z = 40 mm. We constructed a comprehensive 2D model that allows for spatial reaction rates analysis incorporating crucial reactions, and we validated it to kinetically elucidate this phenomenon. CO2 +M⇌O+CO+M and CO2 +O⇌CO+O2 are the dominant reactions, with the forward reactions prevailing in the plasma region and the backward reactions becoming prominent in the afterglow region. These results allow us to propose an afterglow quenching strategy for performance enhancement, which is further demonstrated through a meticulously developed plasmatron reactor with two-stage cooling. Our approach substantially increases the CO2 conversion (e.g., from 6.6 % to 19.5 % at 3 L/min flow rate) and energy efficiency (from 13.5 % to 28.5 %, again at 3 L/min) and significantly shortens the startup time (from ~ 150 s to 25 s). Our study underscores the critical role of inhibiting recombination reactions in plasma-based CO2 conversion and offers new avenues for performance enhancement. | ||||
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Language | Wos | 001168999200001 | Publication Date | 2024-01-10 | |
Series Editor | Series Title | Abbreviated Series Title | |||
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ISSN | 1385-8947 | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor | 15.1 | Times cited | Open Access | Not_Open_Access | |
Notes | Key Research and Development Program of Zhejiang Province, 2023C03129 ; Vlaamse regering; European Research Council; National Natural Science Foundation of China, 51976191 52276214 ; Horizon 2020 Framework Programme; Fonds De La Recherche Scientifique – FNRS; Fonds Wetenschappelijk Onderzoek, 1101524N ; Vlaams Supercomputer Centrum; Horizon 2020, 101081162 810182 ; European Research Council; | Approved | Most recent IF: 15.1; 2024 IF: 6.216 | ||
Call Number | PLASMANT @ plasmant @c:irua:204352 | Serial | 8993 | ||
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Author | De Meyer, R.; Gorbanev, Y.; Ciocarlan, R.-G.; Cool, P.; Bals, S.; Bogaerts, A. | ||||
Title | Importance of plasma discharge characteristics in plasma catalysis: Dry reforming of methane vs. ammonia synthesis | Type | A1 Journal Article | ||
Year | 2024 | Publication | Chemical Engineering Journal | Abbreviated Journal | Chemical Engineering Journal |
Volume | 488 | Issue | Pages | 150838 | |
Keywords | A1 Journal Article; Gas conversion Dry reforming of methane Ammonia Microdischarges Dielectric barrier discharge; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ; | ||||
Abstract | Plasma catalysis is a rapidly growing field, often employing a packed-bed dielectric barrier discharge plasma reactor. Such dielectric barrier discharges are complex, especially when a packing material (e.g., a catalyst) is introduced in the discharge volume. Catalysts are known to affect the plasma discharge, though the underlying mechanisms influencing the plasma physics are not fully understood. Moreover, the effect of the catalysts on the plasma discharge and its subsequent effect on the overall performance is often overlooked. In this work, we deliberately design and synthesize catalysts to affect the plasma discharge in different ways. These Ni or Co alumina-based catalysts are used in plasma-catalytic dry reforming of methane and ammonia synthesis. Our work shows that introducing a metal to the dielectric packing can affect the plasma discharge, and that the distribution of the metal is crucial in this regard. Further, the altered discharge can greatly influence the overall performance. In an atmospheric pressure dielectric barrier discharge reactor, this apparently more uniform plasma yields a significantly better performance for ammonia synthesis compared to the more conventional filamentary discharge, while it underperforms in dry reforming of methane. This study stresses the importance of analyzing the plasma discharge in plasma catalysis experiments. We hope this work encourages a more critical view on the plasma discharge characteristics when studying various catalysts in a plasma reactor. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | Publication Date | 2024-03-30 | ||
Series Editor | Series Title | Abbreviated Series Title | |||
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ISSN | 1385-8947 | ISBN | Additional Links | UA library record | |
Impact Factor | 15.1 | Times cited | Open Access | ||
Notes | This research was supported through long-term structural funding (Methusalem FFB15001C) and by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme with grant agreement No 810182 (SCOPE ERC Synergy project) and with grant agreement No 815128 (REALNANO). We acknowledge the practical contribution of Senne Van Doorslaer. | Approved | Most recent IF: 15.1; 2024 IF: 6.216 | ||
Call Number | PLASMANT @ plasmant @c:irua:205154 | Serial | 9115 | ||
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Author | Maerivoet, S.; Tsonev, I.; Slaets, J.; Reniers, F.; Bogaerts, A. | ||||
Title | Coupled multi-dimensional modelling of warm plasmas: Application and validation for an atmospheric pressure glow discharge in CO2/CH4/O2 | Type | A1 Journal Article | ||
Year | 2024 | Publication | Chemical Engineering Journal | Abbreviated Journal | Chemical Engineering Journal |
Volume | 492 | Issue | Pages | 152006 | |
Keywords | A1 Journal Article; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ; | ||||
Abstract | To support experimental research into gas conversion by warm plasmas, models should be developed to explain the experimental observations. These models need to describe all physical and chemical plasma properties in a coupled way. In this paper, we present a modelling approach to solve the complete set of assumed relevant equations, including gas flow, heat balance and species transport, coupled with a rather extensive chemistry set, consisting of 21 species, obtained by reduction of a more detailed chemistry set, consisting of 41 species. We apply this model to study the combined CO2 and CH4 conversion in the presence of O2, in a direct current atmospheric pressure glow discharge. Our model can predict the experimental trends, and can explain why higher O2 fractions result in higher CH4 conversion, namely due to the higher gas temperature, rather than just by additional chemical reactions. Indeed, our model predicts that when more O2 is added, the energy required to reach any set temperature (i.e., the enthalpy) drops, allowing the system to reach higher temperatures with similar amounts of energy. This is in turn related to the higher H2O fraction and lower H2 fraction formed in the plasma, as demonstrated by our model. Altogether, our new self-consistent model can capture the main physics and chemistry occurring in this warm plasma, which is an important step towards predictive modelling for plasma-based gas conversion. | ||||
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Language | Wos | Publication Date | 2024-05-09 | ||
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ISSN | 1385-8947 | ISBN | Additional Links | ||
Impact Factor | 15.1 | Times cited | Open Access | ||
Notes | This research was supported by the Excellence of Science FWO-FNRS project (FWO grant ID G0I1822N; EOS ID 40007511) and the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement No. 810182–SCOPE ERC Synergy project, and grant agreement No. 101081162–PREPARE ERC Proof of Concept project). computational resources and services used in this work were provided by the HPC core facility CalcUA of the Universiteit Antwerpen, and VSC (Flemish Supercomputer Center), funded by the Research Foundation – Flanders (FWO) and the Flemish Government. | Approved | Most recent IF: 15.1; 2024 IF: 6.216 | ||
Call Number | PLASMANT @ plasmant @ | Serial | 9132 | ||
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Author | Özen, M.; Mertens, M.; Snijkers, F.; Van Tendeloo, G.; Cool, P. | ||||
Title | Texturing of hydrothermally synthesized BaTiO3 in a strong magnetic field by slip casting | Type | A1 Journal article | ||
Year | 2016 | Publication | Ceramics international | Abbreviated Journal | Ceram Int |
Volume | 42 | Issue | 42 | Pages | 5382-5390 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA) | ||||
Abstract | Barium titanate powder was processed by slip casting in a rotating strong magnetic field of 9.4 T. The orientation factor of the sintered compact was analyzed by the X-ray diffraction technique and the microstructure (grain-size) was analyzed by scanning electron microscope. The hydrothermally prepared barium titanate was used as matrix material and the molten-salt synthesized barium titanate, with a larger particle-size, was used as template for the templated grain-growth process. Addition of large template particles was observed to increase the orientation factor of the sintered cast (5 vol% loading). Template particles acted as starting grains for the abnormal grain-growth process and the average grain-size was increased after sintering. Increasing the solid loading (15 vol%) resulted in a similar orientation factor with a decrease of the average grain size by more than half. However, addition of templates to the 15 vol% cast had a negative effect on the orientation factor. The impingement of growing particles was stated as the primary cause of particle misorientation resulting in a low orientation factor after sintering. Different heating conditions were tested and it was determined that a slow heating rate gave the highest orientation factor, the smallest average grain-size and the highest relative density. (C) 2015 Elsevier Ltd and Techna Group S.r.l. All rights reserved. | ||||
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Publisher | Place of Publication | Barking | Editor | ||
Language | Wos | 000369460500098 | Publication Date | 2015-12-23 | |
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ISSN | 0272-8842 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.986 | Times cited | 11 | Open Access | |
Notes | Approved | Most recent IF: 2.986 | |||
Call Number | UA @ lucian @ c:irua:132228 | Serial | 4260 | ||
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Author | Panzic, I.; Mandic, V.; Mangalam, J.; Rath, T.; Radovanovic-Peric, F.; Gaboardi, M.; De Coen, B.; Bals, S.; Schrenker, N. | ||||
Title | In-situ structural degradation study of quadruple-cation perovskite solar cells with nanostructured charge transfer layer | Type | A1 Journal article | ||
Year | 2023 | Publication | Ceramics international | Abbreviated Journal | |
Volume | 49 | Issue | 14b | Pages | 24475-24486 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | We investigated the structural stability of perovskite solar cells (PSCs) in n-i-p configuration comprising a rubidium-caesium-methylammonium-formamidinium (Rb-Cs-MA-FA) lead iodide/bromide perovskite absorber, interfaced with nanostructured ZnO-nanorod (NR) or mesostructured (MS) TiO2 electron transfer layers (ETL). An in-situ setup was established comprising synchrotron grazing incidence diffraction (GID) and Raman spectroscopy as a function of temperature under ambient and isothermal conditions; measurements of current-voltage (IV) characteristics and electron microscopic investigations were conducted discretely.The aging of the solar cells was performed at ambient conditions or at elevated temperatures directly in the in -situ measurement setup. The diffraction depth profiling results point to different degradation rates for different ETLs; moreover, electron microscopy and atomic force microscopy, as well as energy dispersive spectroscopy clarified surface conditions in terms of the extent of the degradation. Scanning transmission electron microscopy of lamellas, derived by dual beam microscopy, revealed that the origin of the degradation lay in the ETL/ absorber interface. For the case of the nanostructured zincite, the perovskite absorber contained many voids, leading to the conclusion that the investigated quadruple perovskite absorber showed limited compatibility with ZnO NR ETL due to a higher number of defects. Morphological defects promoted the absorber degradation and nullified the advantages initially achieved by nanostructuring. The exchange of the ZnO NR ETL with MS TiO2 improved the stability parameters of the absorber layer. | ||||
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Language | Wos | 001021057200001 | Publication Date | 2022-12-25 | |
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ISSN | 0272-8842; 1873-3956 | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor | 5.2 | Times cited | Open Access | OpenAccess | |
Notes | This work has been funded by the projects PZS-2019-02-1555 PV-WALL in Research Cooperability Program of the Croatian Science Foundation funded by the European Union from the European Social Fund under the Operational Programme Efficient Human Resources 2014-2020 (perovskite solar cells) , UIP-2019-04-2367 SLIPPERY SLOPE of the Croatian Science Foundation (nanostructured titania and zincite constituents) , KK.01.2.1.02.0316 “ The development of the technical solution for energy saving using VIS -transparent or semi-transparent and IR-reflective thin-films” by the European Regional Development Fund (ERDF) (characterisation of thin-films) , 20190571 and 20190516 at Elettra Synchrotron, ICM-2019-13220 in Ernst Mach program of the OeAD-GmbH, and E210900588 in the EUSMI program. The group of prof Gregor Trimmel of the ICTM, NAWI Graz, the beam- line scientists of the MCX beamline of the Elettra synchrotron, and FIB- STEM researchers of the Faculty of Science, University of Antwerp, are gratefully acknowledged for collaboration and instrument access. The financial sustenance of the University of Zagreb is gratefully acknowledged. | Approved | Most recent IF: 5.2; 2023 IF: 2.986 | ||
Call Number | UA @ admin @ c:irua:197806 | Serial | 8885 | ||
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Author | Peng, L.; Kassotaki, E.; Liu, Y.; Sun, J.; Dai, X.; Pijuan, M.; Rodriguez-Roda, I.; Buttiglieri, G.; Ni, B.-J. | ||||
Title | Modelling cometabolic biotransformation of sulfamethoxazole by an enriched ammonia oxidizing bacteria culture | Type | A1 Journal article | ||
Year | 2017 | Publication | Chemical engineering science | Abbreviated Journal | |
Volume | 173 | Issue | Pages | 465-473 | |
Keywords | A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL) | ||||
Abstract | Antibiotics such as sulfamethoxazole (SFX) are environmentally hazardous after being released into the aquatic environment and challenges remain in the development of engineered prevention strategies. In this work, a mathematical model was developed to describe and evaluate cometabolic biotransformation of SFX and its transformation products (TPs) in an enriched ammonia oxidizing bacteria (AOB) culture. The growth-linked cometabolic biodegradation by AOB, non-growth transformation by AOB and nongrowth transformation by heterotrophs were considered in the model framework. The production of major TPs comprising 4-Nitro-SFX, Desamino-SFX and N-4-Acetyl-SFX was also specifically modelled. The validity of the model was demonstrated through testing against literature reported data from extensive batch tests, as well as from long-term experiments in a partial nitritation sequencing batch reactor (SBR) and in a combined SBR + membrane aerated biofilm reactor performing nitrification/denitrification. Modelling results revealed that the removal efficiency of SFX increased with the increase of influent ammonium concentration, whereas the influent organic matter, hydraulic retention time and solid retention time exerted a limited effect on SFX biodegradation with the removal efficiencies varying in a narrow range. The variation of influent SFX concentration had no impact on SFX removal efficiency. The established model framework enables interpretation of a range of experimental observations on SFX biodegradation and helps to identify the optimal conditions for efficient removal. (C) 2017 Elsevier Ltd. All rights reserved. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000411764200039 | Publication Date | 2017-08-14 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0009-2509 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | Times cited | Open Access | |||
Notes | Approved | no | |||
Call Number | UA @ admin @ c:irua:146629 | Serial | 8267 | ||
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Author | Andersen, Ja.; van 't Veer, K.; Christensen, Jm.; Østberg, M.; Bogaerts, A.; Jensen, Ad. | ||||
Title | Ammonia decomposition in a dielectric barrier discharge plasma: Insights from experiments and kinetic modeling | Type | A1 Journal article | ||
Year | 2023 | Publication | Chemical engineering science | Abbreviated Journal | |
Volume | 271 | Issue | Pages | 118550 | |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Utilizing ammonia as a storage medium for hydrogen is currently receiving increased attention. A possible method to retrieve the hydrogen is by plasma-catalytic decomposition. In this work, we combined an experimental study, using a dielectric barrier discharge plasma reactor, with a plasma kinetic model, to get insights into the decomposition mechanism. The experimental results revealed a similar effect on the ammonia conversion when changing the flow rate and power, where increasing the specific energy input (higher power or lower flow rate) gave an increased conversion. A conversion as high as 82 % was achieved at a specific energy input of 18 kJ/Nl. Furthermore, when changing the discharge volume from 31 to 10 cm3, a change in the plasma distribution factor from 0.2 to 0.1 was needed in the model to best describe the conversions of the experiments. This means that a smaller plasma volume caused a higher transfer of energy through micro-discharges (non-uniform plasma), which was found to promote the decomposition of ammonia. These results indicate that it is the collisions between NH3 and the high-energy electrons that initiate the decomposition. Moreover, the rate of ammonia destruction was found by the model to be in the order of 1022 molecules/(cm3 s) during the micro-discharges, which is 5 to 6 orders of magnitude higher than in the afterglows. A considerable re-formation of ammonia was found to take place in the afterglows, limiting the overall conversion. In addition, the model revealed that implementation of packing material in the plasma introduced high concentrations of surface-bound hydrogen atoms, which introduced an additional ammonia re-formation pathway through an Eley-Rideal reaction with gas phase NH2. Furthermore, a more uniform plasma is predicted in the presence of MgAl2O4, which leads to a lower average electron energy during micro-discharges and a lower conversion (37 %) at a comparable residence time for the plasma alone (51 %). | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000946293200001 | Publication Date | 2023-02-09 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0009-2509 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.7 | Times cited | Open Access | OpenAccess | |
Notes | We thank Topsoe A/S for providing the packing material used, the research group PLASMANT (UAntwerpen) for sharing their plasma kinetic model and allowing us to perform the calculations on their clusters, and the Department of Chemical and Biochemical Engineering, Technical University of Denmark, for funding this project. | Approved | Most recent IF: 4.7; 2023 IF: 2.895 | ||
Call Number | PLASMANT @ plasmant @c:irua:195204 | Serial | 7237 | ||
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Author | Meng, S.; Li, S.; Sun, S.; Bogaerts, A.; Liu, Y.; Yi, Y. | ||||
Title | NH3 decomposition for H2 production by thermal and plasma catalysis using bimetallic catalysts | Type | A1 Journal article | ||
Year | 2024 | Publication | Chemical engineering science | Abbreviated Journal | Chemical Engineering Science |
Volume | 283 | Issue | Pages | 119449 | |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Plasma catalysis has emerged as a promising approach for driving thermodynamically unfavorable chemical reactions. Nevertheless, comprehending the mechanisms involved remains a challenge, leading to uncertainty about whether the optimal catalyst in plasma catalysis aligns with that in thermal catalysis. In this research, we explore this question by studying monometallic catalysts (Fe, Co, Ni and Mo) and bimetallic catalysts (Fe-Co, Mo- Co, Fe-Ni and Mo-Ni) in both thermal catalytic and plasma catalytic NH3 decomposition. Our findings reveal that the Fe-Co bimetallic catalyst exhibits the highest activity in thermal catalysis, the Fe-Ni bimetallic catalyst outperforms others in plasma catalysis, indicating a discrepancy between the optimal catalysts for the two catalytic modes in NH3 decomposition. Comprehensive catalyst characterization, kinetic analysis, temperature program surface reaction experiments and plasma diagnosis are employed to discuss the key factors influencing NH3 decomposition performance. |
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Publisher | Place of Publication | Editor | |||
Language | Wos | 001105312500001 | Publication Date | 2023-10-28 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0009-2509 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.7 | Times cited | Open Access | Not_Open_Access | |
Notes | Universiteit Antwerpen, 32249 ; National Natural Science Foundation of China, 21503032 ; PetroChina Innovation Foundation, 2018D-5007-0501 ; | Approved | Most recent IF: 4.7; 2024 IF: 2.895 | ||
Call Number | PLASMANT @ plasmant @c:irua:201009 | Serial | 8967 | ||
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Author | Peng, L.; Dai, X.; Liu, Y.; Sun, J.; Song, S.; Ni, B.-J. | ||||
Title | Model-based assessment of estrogen removal by nitrifying activated sludge | Type | A1 Journal article | ||
Year | 2018 | Publication | Chemosphere | Abbreviated Journal | |
Volume | 197 | Issue | Pages | 430-437 | |
Keywords | A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL) | ||||
Abstract | Complete removal of estrogens such as estrone (E1), estradiol (E2), estriol (E3) and ethinylestradiol (EE2) in wastewater treatment is essential since their release and accumulation in natural water bodies are giving rise to environment and health issues. To improve our understanding towards the estrogen bioremediation process, a mathematical model was proposed for describing estrogen removal by nitrifying activated sludge. Four pathways were involved in the developed model: i) biosorption by activated sludge flocs; ii) cometabolic biodegradation linked to ammonia oxidizing bacteria (AOB) growth; iii) non growth biodegradation by AOB; and iv) biodegradation by heterotrophic bacteria (HB). The degradation kinetics was implemented into activated sludge model (ASM) framework with consideration of interactions between substrate update and microorganism growth as well as endogenous respiration. The model was calibrated and validated by fitting model predictions against two sets of batch experimental data under different conditions. The model could satisfactorily capture all the dynamics of nitrogen, organic matters (COD), and estrogens. Modeling results suggest that for El, E2 and EE2, AOB-linked biodegradation is dominant over biodegradation by HB at all investigated COD dosing levels. However, for E3, the increase of COD dosage triggers a shift of dominant pathway from AOB biodegradation to HB biodegradation. Adsorption becomes the main contributor to estrogen removal at high biomass concentrations. (C) 2018 Elsevier Ltd. All rights reserved. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000426231900049 | Publication Date | 2018-01-10 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0045-6535; 1879-1298 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | Times cited | Open Access | |||
Notes | Approved | no | |||
Call Number | UA @ admin @ c:irua:149842 | Serial | 8259 | ||
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Author | Castanheiro, A.; Joos, P.; Wuyts, K.; De Wael, K.; Samson, R. | ||||
Title | Leaf-deposited semi-volatile organic compounds (SVOCs) : an exploratory study using GCxGC-TOFMS on leaf washing solutions | Type | A1 Journal article | ||
Year | 2019 | Publication | Chemosphere | Abbreviated Journal | Chemosphere |
Volume | 214 | Issue | 214 | Pages | 103-110 |
Keywords | A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) | ||||
Abstract | Airborne particulate matter (PM) includes semi-volatile organic compounds (SVOCs), which can be deposited on vegetation matrices such as plant leaves. In alternative to air-point measurements or artificial passive substrates, leaf monitoring offers a cost-effective, time-integrating means of assessing local air quality. In this study, leaf washing solutions from ivy (Hedera hibernica) leaves exposed during one-month at different land use classes were explored via comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry (GCxGC-TOFMS). The composition of leaf-deposited SVOCs, corrected for those of unexposed leaves, was compared against routinely monitored pollutants concentrations (PM10, PM2.5, O3, NO2, SO2) measured at co-located air monitoring stations. The first study on leaf-deposited SVOCs retrieved from washing solutions, herein reported, delivered a total of 911 detected compounds. While no significant land use (rural, urban, industrial, traffic, mixed) effects were observed, increasing exposure time (from one to 28 days) resulted in a higher number and diversity of SVOCs, suggesting cumulative time-integration to be more relevant than local source variations between sites. After one day, leaf-deposited SVOCs were mainly due to alcohols, N-containing compounds, carboxylic acids, esters and lactones, while ketones, diketones and hydrocarbons compounds gained relevance after one week, and phenol compounds after one month. As leaf-deposited SVOCs became overall more oxidized throughout exposure time, SVOCs transformation or degradation at the leaf surface is suggested to be an important phenomenon. This study confirmed the applicability of GCxGC-TOFMS to analyze SVOCs from leaf washing solutions, further research should include validation of the methodology and comparison with atmospheric organic pollutants. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000449891300013 | Publication Date | 2018-09-13 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0045-6535; 1879-1298 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.208 | Times cited | Open Access | ||
Notes | ; The authors thank the Flemish Environment Agency (VMM) for their collaboration and air quality data; Sam Dekkers and Jonathan Van Waeyenbergh for their help with sample collection. The study was performed using a study set-up funded by the Special Research Fund of the University of Antwerp (KPBOF 2014, no. FFB 140090 'Tree leaf surface properties as dynamic drivers of particulate matter-leaf interaction and phyllosphere microbial communities'). A.C. acknowledges the Research Foundation Flanders (FWO) for her SB PhD fellowship. ; | Approved | Most recent IF: 4.208 | ||
Call Number | UA @ admin @ c:irua:153509 | Serial | 5692 | ||
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Author | Van Winckel, T.; Liu, X.; Vlaeminck, S.E.; Takács, I.; Al-Omari, A.; Sturm, B.; Kjellerup, B.V.; Murthy, S.N.; De Clippeleir, H. | ||||
Title | Overcoming floc formation limitations in high-rate activated sludge systems | Type | A1 Journal article | ||
Year | 2019 | Publication | Chemosphere | Abbreviated Journal | |
Volume | 215 | Issue | Pages | 342-352 | |
Keywords | A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) | ||||
Abstract | High-rate activated sludge (HRAS) is an essential cornerstone of the pursuit towards energy positive sewage treatment through maximizing capture of organics. The capture efficiency heavily relies on the degree of solid separation achieved in the clarifiers. Limitations in the floc formation process commonly emerge in HRAS systems, with detrimental consequences for the capture of organics. This study pinpointed and overcame floc formation limitations present in full-scale HRAS reactors. Orthokinetic flocculation tests were performed with varying shear, sludge concentration, and coagulant or flocculant addition. These were analyzed with traditional and novel settling parameters and extracellular polymeric substances (EPS) measurements. HRAS was limited by insufficient collision efficiency and occurred because the solids retention time (SRT) was short and colloid loading was high. The limitation was predominantly caused by impaired flocculation rather than coagulation. In addition, the collision efficiency limitation was driven by EPS composition (low protein over polysaccharide ratio) instead of total EPS amount. Collision efficiency limitation was successfully overcome by bio-augmenting sludge from a biological nutrient removal reactor operating at long SRT which did not show any floc formation limitations. However, this action brought up a floc strength limitation. The latter was not correlated with EPS composition, but rather EPS amount and hindered settling parameters, which determined floc morphology. With this, an analysis toolkit was proposed that will enable design engineers and operators to tackle activated solid separation challenges found in HRAS systems and maximize the recovery potential of the process. (C) 2018 Elsevier Ltd. All rights reserved. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000450383400038 | Publication Date | 2018-10-01 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0045-6535; 1879-1298 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | Times cited | Open Access | |||
Notes | Approved | no | |||
Call Number | UA @ admin @ c:irua:153978 | Serial | 8350 | ||
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Author | Van Winckel, T.; Ngo, N.; Sturm, B.; Al-Omari, A.; Wett, B.; Bott, C.; Vlaeminck, S.E.; De Clippeleir, H. | ||||
Title | Enhancing bioflocculation in high-rate activated sludge improves effluent quality yet increases sensitivity to surface overflow rate | Type | A1 Journal article | ||
Year | 2022 | Publication | Chemosphere | Abbreviated Journal | Chemosphere |
Volume | 308 | Issue | 2 | Pages | 136294-11 |
Keywords | A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) | ||||
Abstract | High-rate activated sludge (HRAS) relies on good bioflocculation and subsequent solid-liquid separation to maximize the capture of organics. However, full-scale applications often suffer from poor and unpredictable effluent suspended solids (ESS). While the biological aspects of bioflocculation are thoroughly investigated, the effects of fines (settling velocity < 0.6 m3/m2/h), shear and surface overflow rate (SOR) are unclear. This work tackled the impact of fines, shear, and SOR on the ESS in absence of settleable influent solids. This was assessed on a full-scale HRAS step-feed (SF) and pilot-scale HRAS contact-stabilization (CS) configuration using batch settling tests, controlled clarifier experiments, and continuous operation of reactors. Fines contributed up to 25% of the ESS in the full-scale SF configuration. ESS decreased up to 30 mg TSS/L when bioflocculation was enhanced with the CS configuration. The feast-famine regime applied in CS promoted the production of high-quality extracellular polymeric substances (EPS). However, this resulted in a narrow and unfavorable settling velocity distribution, with 50% ± 5% of the sludge mass settling between 0.6 and 1.5 m3/m2/h, thus increasing sensitivity towards SOR changes. A low shear environment (20 s−1) before the clarifier for at least one min was enough to ensure the best possible settling velocity distribution, regardless of prior shear conditions. Overall, this paper provides a more complete view on the drivers of ESS in HRAS systems, creating the foundation for the design of effective HRAS clarifiers. Tangible recommendations are given on how to manage fines and establish the optimal settling velocity of the sludge. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000863979600006 | Publication Date | 2022-09-06 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0045-6535; 1879-1298 | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor | 8.8 | Times cited | Open Access | OpenAccess | |
Notes | Approved | Most recent IF: 8.8 | |||
Call Number | UA @ admin @ c:irua:190187 | Serial | 7154 | ||
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Author | Kelly, S.; Verheyen, C.; Cowley, A.; Bogaerts, A. | ||||
Title | Producing oxygen and fertilizer with the Martian atmosphere by using microwave plasma | Type | A1 Journal article | ||
Year | 2022 | Publication | Chem | Abbreviated Journal | Chem |
Volume | 8 | Issue | 10 | Pages | 2797-2816 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | We explorethepotentialofmicrowave(MW)-plasma-based in situ utilizationoftheMartianatmospherewithafocusonthenovelpos- sibilityoffixingN2 forfertilizerproduction. Conversioninasimulant plasma (i.e., 96% CO2, 2% N2, and 2% Ar),performedunderen- ergyconditionssimilartothoseoftheMarsOxygen In Situ Resource UtilizationExperiment(MOXIE),currentlyonboardNASA’sPerse- verancerover,demonstratesthatO/O2 formedthroughCO2 dissociation facilitatesthefixationoftheN2 fractionviaoxidationtoNOx. PromisingproductionratesforO2, CO,andNOx of 47.0,76.1,and 1.25g/h,respectively,arerecordedwithcorrespondingenergy costs of0.021,0.013,and0.79kWh/g,respectively.Notably,O2 productionratesare 30 timeshigherthanthosedemonstrated by MOXIE,whiletheNOx production raterepresentsan 7% fixa- tionoftheN2 fraction presentintheMartian atmosphere.MW- plasma-basedconversionthereforeshowsgreatpotentialasan in situ resourceutilization(ISRU)technologyonMarsinthatitsimulta- neouslyfixesN2 and producesO2. |
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000875346600005 | Publication Date | 2022-08-22 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2451-9294 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 23.5 | Times cited | Open Access | OpenAccess | |
Notes | the Euro- pean Marie Skłodowska-Curie Individual Fellowship ‘‘PENFIX’’ within Horizon 2020 (grant no. 838181), the European Research Council (ERC) under the European Union’s Horizon 2020 Research and Innovation Program (grant no. 810182; SCOPE ERC Synergy project), and the Excellence of Science FWO-FNRS project (FWO grant no. GoF9618n and EOS no. 30505023). C.V. was supported by a FWO aspirant PhD fellowship (grant no. 1184820N). The calculations were per- formed with the Turing HPC infrastructure at the CalcUA core facility of the Univer- siteit Antwerpen (Uantwerpen), a division of the Flemish Supercomputer Centre VSC, funded by the Hercules Foundation, the Flemish government (department EWI), and Uantwerpen. | Approved | Most recent IF: 23.5 | ||
Call Number | PLASMANT @ plasmant @c:irua:192174 | Serial | 7243 | ||
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