Enhanced Removal of Dissolved Hg(II), Cd(II), and Au(III) from Water by Bacillus subtilis Bacterial Biomass Containing an Elevated Concentration of Sulfhydryl Sites
Autor: | Qiang Yu, Jeremy B. Fein |
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Rok vydání: | 2017 |
Předmět: |
Inorganic chemistry
Biomass Bacillus subtilis 010501 environmental sciences 010402 general chemistry complex mixtures 01 natural sciences Bacterial cell structure Water Purification chemistry.chemical_compound Metals Heavy Environmental Chemistry Ion-exchange resin Volume concentration 0105 earth and related environmental sciences Growth medium biology Water Sorption Mercury General Chemistry Hydrogen-Ion Concentration biology.organism_classification 0104 chemical sciences chemistry Adsorption Bacteria |
Zdroj: | Environmental Science & Technology. 51:14360-14367 |
ISSN: | 1520-5851 0013-936X |
Popis: | In this study, the sorption of Hg(II), Cd(II), and Au(III) onto Bacillus subtilis biomass with an elevated concentration of sulfhydryl sites, induced by adding excess glucose to the growth medium (termed 'High Sulfhydryl Bacillus subtilis' or HSBS) was compared to that onto B. subtilis biomass with a low concentration of sulfhydryl sites (termed 'Low Sulfhydryl Bacillus subtilis' or LSBS) and to sorption onto a commercially available cation exchange resin. Our results show that HSBS exhibits sorption capacities for the three studied metals that are two to five times greater than the sorption capacities of LSBS for these metals. After blocking the bacterial cell envelope sulfhydryl sites using a qBBr treatment, the sorption of the metals onto HSBS was significantly inhibited, indicating that the enhanced sorption onto HSBS was mainly due to the elevated concentration of sulfhydryl sites on the bacteria. A direct comparison of the removal capacity of the HSBS and that of the cation exchange resin for the three metals demonstrates that HSBS, compared to this commercially available resin, exhibits superior sorption capacity and selectivity for the removal of Hg(II), Cd(II), and Au(III), especially in systems with dilute metal concentrations. These results suggest that bacterial sulfhydryl sites control the sorption behavior of these three metals, and therefore biomass with induced high concentrations of sulfhydryl sites represents a promising and low cost biosorbent for the effective removal and recovery of chalcophile heavy metals from aqueous media. |
Databáze: | OpenAIRE |
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