Cd(II) Sorption on Montmorillonite-Humic acid-Bacteria Composites.

ABSTRACT: Soil components (e.g., clays, bacteria and humic substances) are known to produce mineral-organic composites in natural systems. Herein, batch sorption isotherms, isothermal titration calorimetry (ITC), and Cd K-edge EXAFS spectroscopy were applied to investigate the binding characteristics of Cd on montmorillonite(Mont)-humic acid(HA)-bacteria composites. Additive sorption and non-additive Cd(II) sorption behaviour is observed for the binary Mont-bacteria and ternary Mont-HA-bacteria composite, respectively. Specifically, in the ternary composite, the coexistence of HA and bacteria inhibits Cd adsorption, suggesting a "blocking effect" between humic acid and bacterial cells. Large positive entropies (68.1~114.4 J/mol/K), and linear combination fitting of the EXAFS spectra for Cd adsorbed

SUBMITTER: Du H 

PROVIDER: S-EPMC4726142 | biostudies-literature | 2016 Jan

REPOSITORIES: biostudies-literature