Multi-Metal Biosorption Equilibria of Cr(VI), Cu(II), Cd(II), and Fe(III) Ions

Y. Sag* and B. Akcael

Department of Chemical Engineering, Faculty of Engineering, Hacettepe University, 06532 Beytepe, Ankara, Turkey

Received 1 May 2002; accepted 12 October 2002



ABSTRACT

Four-component biosorption equilibria of Cr(VI), Cu(II), Cd(II), and Fe(III) ions were studied using Rhizopus arrhizus. As the multicomponent Langmuir model was able to predict the two ternary subsystems of these metal ions satisfactorily, it was further applied in describing the behavior of the quaternary metal systems. To present a summary of the effect of one metal on the uptake of the other, three-dimensional (3-D) sorption isotherm surfaces were constructed. The apparent equilibrium constant, the biosorption efficiency and the relative coverage of the four metals were in the order Fe³Cr>Cd>Cu.


Keywords: Four-metal biosorption; Chromium(VI); Copper(II); Cadmium(II); Iron(III); Rhizopus arrhizus; Multicomponent Langmuir model



* Corresponding author
   E-mail : yesims@hacettepe.edu.tr