The simultaneous biosorption of three metal ions - chromium(VI), iron(
III) and copper(II) - has been studied using R. arrhizus. The ability
of the fungal biomass to bind three metals simultaneously is shown as
a function of levels of metal concentration and ratios of metals. Sinc
e the initial biosorption rates, equilibrium and ultimate metal remova
l decreased with increasing concentrations of the other metal ions, th
e combined action of Cr(VI), Fe(III) and Cu(II) ions on R. arrhizus wa
s generally found to be antagonistic. Although Cr(VI) ions were adsorb
ed selectively from the ternary metal mixtures, Fe(III) ions competed
strongly with Cr(VI) ions to bind to active sites on the fungus. (C) 1
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