Simultaneous removal of chromium(VI) and tetracycline hydrochloride from simulated wastewater by nanoscale zero-valent iron/copper–activated persulfate
Autor: | Tiecheng Wang, Hong Qiang, Zengqiang Zhang, Dongli Liang, Rongjie Chu, Hui Wang, Shibin Hu, Guangzhou Qu |
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Rok vydání: | 2020 |
Předmět: |
Zerovalent iron
Chemistry Health Toxicology and Mutagenesis chemistry.chemical_element General Medicine 010501 environmental sciences Persulfate 01 natural sciences Pollution Copper Metal Galvanic corrosion Chromium visual_art visual_art.visual_art_medium Galvanic cell Environmental Chemistry Bimetallic strip 0105 earth and related environmental sciences Nuclear chemistry |
Zdroj: | Environmental Science and Pollution Research. 27:40826-40836 |
ISSN: | 1614-7499 0944-1344 |
DOI: | 10.1007/s11356-020-10120-8 |
Popis: | In this paper, metallic copper (Cu) was supported on nanoscale zero-valent iron (nZVI) to form a nanoscale bimetallic composite (nZVI-Cu), which was used to activate persulfate (PS) to simultaneously remove the compound contaminants Cr(VI) and tetracycline hydrochloride (TCH) in simulated wastewater. nZVI, nZVI-Cu, and nZVI-Cu-activated PS (nZVI-Cu/PS) were characterized by SEM, TEM, XRD, and XPS. The effects of the bimetallic composite on Cr(VI) and TCH removal were compared in the nZVI, nZVI-activated PS (nZVI/PS), nZVI-Cu, and nZVI-Cu/PS systems. The results showed that nZVI and Cu can form a nanobimetallic system, which can create galvanic cells; thus, the galvanic corrosion of nZVI and the transfer of electrons are accelerated. For a single contaminant, the removal efficiency of Cr(VI) and TCH is the highest when nZVI is loaded with 3 wt% and 1 wt% Cu, respectively. The ratio of nZVI-Cu with 3 wt% Cu to PS is 7:1, and the removal efficiency of Cr(VI) and TCH compound contaminants is ~ 100% after 60 min under acidic conditions, which indicates that the Cr(VI) reduction and TCH oxidation were complete in the nZVI-Cu/PS system. The mechanisms of simultaneous removal of Cr(VI) and TCH in the nZVI-Cu/PS system are proposed. The removal of Cr is because of the adsorption-reduction effects of the nZVI-Cu bimetallic material. The degradation of TCH is mainly due to the action of oxidative free radicals generated by Fe2+-activated PS. The free radical capture experiments showed that SO- 4· plays a major role in the process of TCH degradation. |
Databáze: | OpenAIRE |
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