Monitoring Cr(VI) photoreduction at different depths by operando low-field NMR relaxometry
Chromium (VI) (Cr(VI)), a toxic metal ion, is widely present in industrial wastewater. To reduce the contamination of Cr(VI), many technologies for the photocatalytic reduction of Cr(VI) to Cr(III) have been developed in the past decades. However, the practical application of photocatalysts for the...
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| Format: | Article |
| Language: | English |
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KeAi Communications Co. Ltd.
2022-08-01
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| Series: | Magnetic Resonance Letters |
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| Online Access: | http://www.sciencedirect.com/science/article/pii/S2772516222000249 |
| _version_ | 1797980239587966976 |
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| author | Beibei Xu Jingxian Dong Xuelu Wang Yefeng Yao |
| author_facet | Beibei Xu Jingxian Dong Xuelu Wang Yefeng Yao |
| author_sort | Beibei Xu |
| collection | DOAJ |
| description | Chromium (VI) (Cr(VI)), a toxic metal ion, is widely present in industrial wastewater. To reduce the contamination of Cr(VI), many technologies for the photocatalytic reduction of Cr(VI) to Cr(III) have been developed in the past decades. However, the practical application of photocatalysts for the reduction of Cr(VI) in wastewater treatment is often hindered by the complicated photoreduction processes due to the sedimentation and stratification of catalyst particles that present during the treatment of the wastewater. Probing and understanding the influences of the sedimentation and stratification of the catalyst particles on the photoreduction processes are long-term challenges in the field. Herein, we demonstrate that this issue can be solved by using layer location integrated low-field time-domain nuclear magnetic resonance (LF-NMR) relaxometry. With paramagnetic Cr (III) cation as the molecular probe, we successfully monitored the Cr(VI) photoreduction processes by operando probing the 1H T2 relaxation time of the photoreduction systems. The influences of catalyst sedimentation and the light wavelength on photocatalysis were studied and discussed. The results showed the great potential of LF-NMR relaxometry in the study of Cr (VI) photoreduction processes during industrial wastewater treatments. |
| first_indexed | 2024-04-11T05:51:23Z |
| format | Article |
| id | doaj.art-a89369e42c6c46798dc8043c5518cdfc |
| institution | Directory Open Access Journal |
| issn | 2772-5162 |
| language | English |
| last_indexed | 2024-04-11T05:51:23Z |
| publishDate | 2022-08-01 |
| publisher | KeAi Communications Co. Ltd. |
| record_format | Article |
| series | Magnetic Resonance Letters |
| spelling | doaj.art-a89369e42c6c46798dc8043c5518cdfc2022-12-22T04:42:03ZengKeAi Communications Co. Ltd.Magnetic Resonance Letters2772-51622022-08-0123170176Monitoring Cr(VI) photoreduction at different depths by operando low-field NMR relaxometryBeibei Xu0Jingxian Dong1Xuelu Wang2Yefeng Yao3Physics Department & Shanghai Key Laboratory of Magnetic Resonance, School of Physics and Materials Science, East China Normal University, North Zhongshan Road 3663, Shanghai, 200062, ChinaPhysics Department & Shanghai Key Laboratory of Magnetic Resonance, School of Physics and Materials Science, East China Normal University, North Zhongshan Road 3663, Shanghai, 200062, ChinaCorresponding author.; Physics Department & Shanghai Key Laboratory of Magnetic Resonance, School of Physics and Materials Science, East China Normal University, North Zhongshan Road 3663, Shanghai, 200062, ChinaCorresponding author.; Physics Department & Shanghai Key Laboratory of Magnetic Resonance, School of Physics and Materials Science, East China Normal University, North Zhongshan Road 3663, Shanghai, 200062, ChinaChromium (VI) (Cr(VI)), a toxic metal ion, is widely present in industrial wastewater. To reduce the contamination of Cr(VI), many technologies for the photocatalytic reduction of Cr(VI) to Cr(III) have been developed in the past decades. However, the practical application of photocatalysts for the reduction of Cr(VI) in wastewater treatment is often hindered by the complicated photoreduction processes due to the sedimentation and stratification of catalyst particles that present during the treatment of the wastewater. Probing and understanding the influences of the sedimentation and stratification of the catalyst particles on the photoreduction processes are long-term challenges in the field. Herein, we demonstrate that this issue can be solved by using layer location integrated low-field time-domain nuclear magnetic resonance (LF-NMR) relaxometry. With paramagnetic Cr (III) cation as the molecular probe, we successfully monitored the Cr(VI) photoreduction processes by operando probing the 1H T2 relaxation time of the photoreduction systems. The influences of catalyst sedimentation and the light wavelength on photocatalysis were studied and discussed. The results showed the great potential of LF-NMR relaxometry in the study of Cr (VI) photoreduction processes during industrial wastewater treatments.http://www.sciencedirect.com/science/article/pii/S2772516222000249PhotocatalysisOperando low-field NMRSlice location integrated low-field NMR relaxometryCr(VI) reductionMolecular probe |
| spellingShingle | Beibei Xu Jingxian Dong Xuelu Wang Yefeng Yao Monitoring Cr(VI) photoreduction at different depths by operando low-field NMR relaxometry Magnetic Resonance Letters Photocatalysis Operando low-field NMR Slice location integrated low-field NMR relaxometry Cr(VI) reduction Molecular probe |
| title | Monitoring Cr(VI) photoreduction at different depths by operando low-field NMR relaxometry |
| title_full | Monitoring Cr(VI) photoreduction at different depths by operando low-field NMR relaxometry |
| title_fullStr | Monitoring Cr(VI) photoreduction at different depths by operando low-field NMR relaxometry |
| title_full_unstemmed | Monitoring Cr(VI) photoreduction at different depths by operando low-field NMR relaxometry |
| title_short | Monitoring Cr(VI) photoreduction at different depths by operando low-field NMR relaxometry |
| title_sort | monitoring cr vi photoreduction at different depths by operando low field nmr relaxometry |
| topic | Photocatalysis Operando low-field NMR Slice location integrated low-field NMR relaxometry Cr(VI) reduction Molecular probe |
| url | http://www.sciencedirect.com/science/article/pii/S2772516222000249 |
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