Improvement of Fe(Ⅲ)/percarbonate system by molybdenum powder and tripolyphosphate: Co-catalytic performance, low oxidant consumption, pH-dependent mechanism.
In: Journal of Hazardous Materials, Jg. 464 (2024-02-15), S. N.PAG
Online
academicJournal
Zugriff:
The homogeneous sodium percarbonate (SPC) systems are limited by narrow pH range, ineffective consumption of oxidant, and weak reusability of catalyst. Herein, molybdenum (Mo) powder and sodium tripolyphosphate (STPP) were selected to overcome these challenges. Sulfamethoxazole (SMX), as a model contaminant, was almost completely degraded in 60 min with higher removal rate (0.1367 min−1) than the Mo or STPP-absent system. In addition, Mo/STPP-Fe(Ⅲ)/SPC system was cost-effective in terms of oxidant consumption, requiring only 0.2 mM SPC. About activation mechanism, the main active species for SMX degradation was pH-dependent, with hydroxyl radical (· OH) as the dominant active species at pH i = 7 and · OH, carbonate radical (CO 3 · -), and superoxide radical (O 2 · -) derived from a series of chain reaction at pH i = 10, respectively. Due to the generation of various electrophilic free radical, the system exhibited excellent performance towards electron-rich pollutants under a wide pH range. Furthermore, Mo exhibited excellent stability and reusability. SMX was degraded through hydroxylation, N-S cleavage, amino and sulfanilamide oxidation into intermediates whose toxicities were evaluated by Toxicity Estimation Software Tool (T.E.S.T.) software. This work provided new insights to Fe/SPC system towards high-efficiency and low consumption treatment of practical application. [Display omitted] • Mo and STPP significantly increased the efficiency of SMX degradation and SPC utilization. • There were differences of active species at different initial pH conditions. • No formation of 1O 2 under initial pH= 10 conditions. • The system exhibited excellent salt tolerance capability and contaminants removal. • The degradation intermediates of SMX were proposed at different initial pH. [ABSTRACT FROM AUTHOR]
Titel: |
Improvement of Fe(Ⅲ)/percarbonate system by molybdenum powder and tripolyphosphate: Co-catalytic performance, low oxidant consumption, pH-dependent mechanism.
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Autor/in / Beteiligte Person: | Zhou, Zhengwei ; Ye, Guojie ; Zong, Yang ; Zhao, Zhenyu ; Wu, Deli |
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Zeitschrift: | Journal of Hazardous Materials, Jg. 464 (2024-02-15), S. N.PAG |
Veröffentlichung: | 2024 |
Medientyp: | academicJournal |
ISSN: | 0304-3894 (print) |
DOI: | 10.1016/j.jhazmat.2023.132924 |
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