Neutron tomography of porous aluminum electrodes used in electrocoagulation of groundwater
In this work, neutron computed tomography (CT) is employed to investigate the dissolution of porous aluminum electrodes during electrocoagulation (EC). Porous electrodes were chosen in efforts to reduce electric power requirements by using larger surface-area electrodes, having both inner and outer...
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Frontiers Media S.A.
2022-11-01
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| Series: | Frontiers in Chemical Engineering |
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| Online Access: | https://www.frontiersin.org/articles/10.3389/fceng.2022.1046627/full |
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| author | G. G. Jang Y. Zhang J. K. Keum J. K. Keum Y. Z. Bootwala M. C. Hatzell D. Jassby C. Tsouris |
| author_facet | G. G. Jang Y. Zhang J. K. Keum J. K. Keum Y. Z. Bootwala M. C. Hatzell D. Jassby C. Tsouris |
| author_sort | G. G. Jang |
| collection | DOAJ |
| description | In this work, neutron computed tomography (CT) is employed to investigate the dissolution of porous aluminum electrodes during electrocoagulation (EC). Porous electrodes were chosen in efforts to reduce electric power requirements by using larger surface-area electrodes, having both inner and outer surface, for the EC process. Neutron CT allowed 3D reconstruction of the porous electrodes, and image analysis provided the volume of each electrode vs. thickness, which can indicate whether the inner surface is effectively involved in EC reactions. For the anode, the volume decreased uniformly throughout the thickness of the electrode, indicating that both the outer and inner surface participated in electrochemical dissolution, while the volume of the cathode increased uniformly vs. thickness, indicating deposition of material on both the outer and inner surface. The attenuation coefficient vs. thickness, increased for both anode and cathode, indicating surface chemistry changes. For the anode, the attenuation coefficient increased slightly but uniformly, probably due to aluminum oxide formation on the surface of the anode. For the cathode, the attenuation coefficient increased more than for the anode and nonuniformly. The higher increase in the attenuation coefficient for the cathode is due to precipitation of aluminum hydroxide on the electrode surface, which added hydrogen. Image analysis also showed that, although the attenuation coefficient increased throughout the thickness of the electrode, most of the hydroxide deposition occurred on the outer surface. Energy analysis showed that porous electrodes can be used to reduce process energy requirements by as much as 4 times compared to solid electrodes. |
| first_indexed | 2024-04-13T17:08:38Z |
| format | Article |
| id | doaj.art-14cc5c5336d84f78ad24fda73a83df32 |
| institution | Directory Open Access Journal |
| issn | 2673-2718 |
| language | English |
| last_indexed | 2024-04-13T17:08:38Z |
| publishDate | 2022-11-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Chemical Engineering |
| spelling | doaj.art-14cc5c5336d84f78ad24fda73a83df322022-12-22T02:38:22ZengFrontiers Media S.A.Frontiers in Chemical Engineering2673-27182022-11-01410.3389/fceng.2022.10466271046627Neutron tomography of porous aluminum electrodes used in electrocoagulation of groundwaterG. G. Jang0Y. Zhang1J. K. Keum2J. K. Keum3Y. Z. Bootwala4M. C. Hatzell5D. Jassby6C. Tsouris7Manufacturing Science Division, Oak Ridge National Laboratory (ORNL), Oak Ridge, TN, United StatesNeutron Scattering Division, ORNL, Oak Ridge, TN, United StatesNeutron Scattering Division, ORNL, Oak Ridge, TN, United StatesCenter for Nanophase Materials Science and Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN, United StatesGeorge W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, United StatesGeorge W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, United StatesDepartment of Civil and Environmental Engineering, Institute of the Environment & Sustainability and California NanoSystems Institute, University of California, Los Angeles, Los Angeles, CA, United StatesManufacturing Science Division, Oak Ridge National Laboratory (ORNL), Oak Ridge, TN, United StatesIn this work, neutron computed tomography (CT) is employed to investigate the dissolution of porous aluminum electrodes during electrocoagulation (EC). Porous electrodes were chosen in efforts to reduce electric power requirements by using larger surface-area electrodes, having both inner and outer surface, for the EC process. Neutron CT allowed 3D reconstruction of the porous electrodes, and image analysis provided the volume of each electrode vs. thickness, which can indicate whether the inner surface is effectively involved in EC reactions. For the anode, the volume decreased uniformly throughout the thickness of the electrode, indicating that both the outer and inner surface participated in electrochemical dissolution, while the volume of the cathode increased uniformly vs. thickness, indicating deposition of material on both the outer and inner surface. The attenuation coefficient vs. thickness, increased for both anode and cathode, indicating surface chemistry changes. For the anode, the attenuation coefficient increased slightly but uniformly, probably due to aluminum oxide formation on the surface of the anode. For the cathode, the attenuation coefficient increased more than for the anode and nonuniformly. The higher increase in the attenuation coefficient for the cathode is due to precipitation of aluminum hydroxide on the electrode surface, which added hydrogen. Image analysis also showed that, although the attenuation coefficient increased throughout the thickness of the electrode, most of the hydroxide deposition occurred on the outer surface. Energy analysis showed that porous electrodes can be used to reduce process energy requirements by as much as 4 times compared to solid electrodes.https://www.frontiersin.org/articles/10.3389/fceng.2022.1046627/fullneutron tomographyelectrocoagulationporous aluminum electrodesgroundwater treatmentneutron imaging |
| spellingShingle | G. G. Jang Y. Zhang J. K. Keum J. K. Keum Y. Z. Bootwala M. C. Hatzell D. Jassby C. Tsouris Neutron tomography of porous aluminum electrodes used in electrocoagulation of groundwater Frontiers in Chemical Engineering neutron tomography electrocoagulation porous aluminum electrodes groundwater treatment neutron imaging |
| title | Neutron tomography of porous aluminum electrodes used in electrocoagulation of groundwater |
| title_full | Neutron tomography of porous aluminum electrodes used in electrocoagulation of groundwater |
| title_fullStr | Neutron tomography of porous aluminum electrodes used in electrocoagulation of groundwater |
| title_full_unstemmed | Neutron tomography of porous aluminum electrodes used in electrocoagulation of groundwater |
| title_short | Neutron tomography of porous aluminum electrodes used in electrocoagulation of groundwater |
| title_sort | neutron tomography of porous aluminum electrodes used in electrocoagulation of groundwater |
| topic | neutron tomography electrocoagulation porous aluminum electrodes groundwater treatment neutron imaging |
| url | https://www.frontiersin.org/articles/10.3389/fceng.2022.1046627/full |
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