The preparation of low-cost and highly efficient functional materials for the cleanup of mercury-contaminated water by adsorption in an environmentally friendly way is of great significance. In this study, thiol-functionalized montmorillonite (BSH-MMT) was prepared by a novel one-step mechanochemical grafting method and applied to aqueous Hg and CHHg adsorption. Characterization results showed that thiol groups were successfully grafted by chemical bonding with Si-OH or broken SiO bonds. The maximum adsorption capacities of BSH-MMT for Hg and CHHg were 104.79 mg g and 39.27 mg g, which were approximately seven- and nine-fold that of pristine MMT, respectively. Adsorption kinetics and isotherm fitting indicated that Hg adsorbs heterogeneously, while CHHg proceeds through monolayer adsorption, both with chemical adsorption as the rate-limiting step. BSH-MMT maintained high adsorption performance over a wide pH range and in the presence of humic acid because of the high affinity of thiol groups toward mercury. The primary adsorption mechanism of thiol-ligand complexation was confirmed by the results of X-ray photoelectron spectroscopy and X-ray absorption spectra, in which a complex structure of bis-coordinated S-Hg-S (2.30 Å distance) was observed. These results demonstrated that mechanochemical grafting is a promising one-step method to prepare thiol-functionalized montmorillonite for effective cleanup of Hg/CHHg contamination in water.
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http://dx.doi.org/10.1016/j.scitotenv.2021.150510 | DOI Listing |
Sci Total Environ
February 2022
Key Laboratory of Original Agro-Environmental Pollution Prevention and Control, Ministry of Agriculture and Rural Affairs (MARA), Agro-Environmental Protection Institute, Tianjin 300191, China; Tianjin Key Laboratory of Agro-Environment and Agro-Product Safety, Agro-Environmental Protection Institute, MARA, Tianjin 300191, China. Electronic address:
The preparation of low-cost and highly efficient functional materials for the cleanup of mercury-contaminated water by adsorption in an environmentally friendly way is of great significance. In this study, thiol-functionalized montmorillonite (BSH-MMT) was prepared by a novel one-step mechanochemical grafting method and applied to aqueous Hg and CHHg adsorption. Characterization results showed that thiol groups were successfully grafted by chemical bonding with Si-OH or broken SiO bonds.
View Article and Find Full Text PDFJ Colloid Interface Sci
March 2020
Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan. Electronic address:
Bull Environ Contam Toxicol
July 2019
Nanjing Xiaozhuang University, Nanjing, 210008, People's Republic of China.
A 3-year pot experiment was carried out to investigate the efficiencies of hydroxyapatite (H), thiol-functionalized bentonite (T) and biochar (B) alone or in combination in remedying a Cd-Pb-contaminated soil. The application of passivating agents reduced the Cd and Pb mobility in acidic soil and enhanced soil microbial community function. The largest reductions in the Cd and Pb acid-soluble portions were observed under H (33.
View Article and Find Full Text PDFJ Hazard Mater
May 2007
Dipartimento di Scienze della Terra, Università di Modena e Reggio Emilia, Largo S. Eufemia 19, I-41100 Modena, Italy.
The interaction between Cd(II) in aqueous solution and two 2:1 expandable clay minerals (i.e., montmorillonite and vermiculite), showing different layer charge, was addressed via batch sorption experiments on powdered clay minerals both untreated and amino acid (cysteine) treated.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!