Influence of anions on metal adsorption by Rhizopus arrhizus biomass.
The presence of anions in solution was found to inhibit the uptake of La3+, Cd2+, Pb2+, UO(2)(2+), and Ag+ by Rhizopus arrhizus biomass. The effects ranged from total inhibition of Cd2+ and Pb2+ uptake at equimolar concentrations of EDTA to no change in uptake of La3+ or UO(2)(2+)at 12-fold molar excesses of CI- or CO(3)(2-). No anion was found to enhance metal uptake levels, and the degree of inhibition generally followed the series: EDTA >or= >or= SO(4)(2)- C1- >or= PO(4)(3)- >or= glutamate >or= C0(3)(2)- The chemical equilibrium model REDEQLP was adapted to treat metal uptake by R. arrhizus biomass and used to predict the effects of anions in solution. Comparisons with the experimental results are made and discussed in light of the assumptions underlying the model.
Tobin
J M
JM
Department of Chemical Engineering, McGill University, 3480 University Street, Montreal, Quebec H3A 2A7.
Cooper
D G
DG
Neufeld
R J
RJ