The effects of Ca2+, Cl- and humic acid (HA) on the removal rates of Pb(II) and Hg(II) in water by zero-valent (ZVI) and the kinetic characteristics were studied, and the removal mechanism of Pb(II) and Hg(II) by ZVI were preliminarily investigated using X-ray diffraction (XRD). The results indicated that the removal mechanism of Pb(II) might mainly be attributed to the adsorption and co-precipitation of ZVI, while that of Hg(II) might mainly be attributed to the oxidation-reduction of ZVI. With the increase of Ca2+ concentration, the removal rates of Hg(II) and Pb(II) showed the trends of gradual increase and slight decrease, respectively. The Hg(II) removal increased with increasing Cl- concentration, whereas no obvious increase in Pb(II) removal was observed. The removal rates of Hg(II) and Pb(II) showed the trends of slow increase and slow decrease with increasing HA concentration, respectively. When Ca2+, Cl- and HA coexisted, the removal rates of Hg(II) and Pb(II) reached 99.71% and 97.95%, respectively. The removal processes of Pb(II) and Hg(II) could be described by pseudo first-order reaction kinetic equations when Ca2+, Cl- and HA existed alone and in combination. The removal rate constant of Pb(II) was the maxinum (0.024 0 min(-1)) when 5 mg x L(-1) HA existed alone, whereas that of Hg(II) was the maximum (0.0169 min(-1)) when 0.80 mmol x L(-1) Ca2+ existed alone.
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Materials (Basel)
January 2025
Division of Applied Chemistry and Biochemistry, National Institute of Technology, Tomakomai College, Nishikioka 443, Tomakomai 059-1275, Hokkaido, Japan.
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Chemistry Department, Faculty of Science, Ain-Shams University, Cairo, 11566, Egypt; Department of Chemistry, Faculty of Science, Galala University, New Galala City, Suez, Egypt. Electronic address:
Background: Electrochemical methods, particularly those utilizing sensors, offer distinct advantages over classical analytical methods. They are cost-effective, compatible with mass fabrication, suitable for remote sensing, and can be designed as handheld analyzers. In this context, MIL-101(Cr)-(COOH)₂@MWCNTs was utilized for the first time as a modifier for GCE for the sensitive voltammetric detection of Pb(II), Cu(II), and Hg(II).
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College of Material, Chemistry and Chemical Engineering, Key Laboratory of Organosilicon Chemistry and Material Technology, Ministry of Education, Hangzhou Normal University, Hangzhou, Zhejiang 311121, China. Electronic address:
Aquaculture organisms may accumulate metals to induce health risks. Compared with the focus on total contents, chemical-specific risk assessment makes reasonable but is rare. Herein, we elucidated occurrence of twelve metal compounds in shrimp and fish (edible muscle, one of major metal-containing and generally targeted organs), water, sediment, and feedstuff from two aquaculture ponds in Zhejiang Province (one of the major aquatic production and consumption areas).
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Residues and Resource Reclamation Centre (R3C), Nanyang Environment and Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, CleanTech One, 637141, Singapore; School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore. Electronic address:
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Engineering Faculty, Department of Environmental and Chemical Engineering, Universidad Nacional de Colombia, Colombia.
In the present work, we report the synthesis and evaluation of a graphite-supported bismuth film working electrode (BiFE) in the simultaneous quantification of Hg(II) and Pb(II) at ppb levels. The BiFE was synthesized in-situ by electrodeposition in 1 M HNO as the supporting electrolyte at -0.5 V potential.
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