Competition of Cd, Cu, and Pb adsorption on goethite
Document Type
Article
Publication Date
1-1-2000
Abstract
Competition of copper, lead, and cadmium adsorption on goethite was studied and found to be dependent on metal ion and oxide surface characteristics. In adsorption edges, ionic strength effects suggested copper, lead, and cadmium are specifically adsorbed on goethite. Metal capacity on the goethite surface was found to increase with metal electronegativity: Cu > Pb > Cd. On the other hand, the equilibrium constant for lead was greater than that of copper, which is in agreement with their hydrated radii (Pb < Cu < Cd). Modeling revealed that the single-site Langmuir isotherm described the Cu-Cd and Pb-Cd adsorption and competition results within the error of the model. Furthermore, although the model provided a good fit for Pb and Cd data in the Pb-Cu and Pb-Cu-Cd systems, it underpredicted copper adsorption. The difference in site densities between copper and lead revealed a set of sites not available for competition. Using this approach where copper affinity is equivalent for both sites, the model provided a good fit for copper adsorption and competition. This study confirms that adsorption competition plays a crucial role in contaminant mobility in the environment.
Identifier
0343484251 (Scopus)
Publication Title
Journal of Environmental Engineering
External Full Text Location
https://doi.org/10.1061/(ASCE)0733-9372(2000)126:1(66)
ISSN
07339372
First Page
66
Last Page
74
Issue
1
Volume
126
Recommended Citation
Christophi, Chris A. and Axe, Lisa, "Competition of Cd, Cu, and Pb adsorption on goethite" (2000). Faculty Publications. 15689.
https://digitalcommons.njit.edu/fac_pubs/15689