title: Multi-metallic modelling for biosorption of binary systems.
abstract: In this paper a specially propagated biomass of Sphaerotilus natans was tested as adsorbent for binary solutions of Cu-Cd, Cu-Pb and Cu--Zn at different equilibrium pH. The experimental results outline the buffering effect of H+ at low pH. which masks the competition among metals. In each binary system the biomass affinity follows the acidic properties of the heavy metals probably due to an ionic exchange mechanism operating among active sites and metals in solution. The experimental results were fitted according to an empirical approach with growing complexity that outlines the inadequacy of the predictive models and the non-ideal interactions among metals.
authors.affiliation: Dipartimento di Chimica, Facoltà di S.M.F. N., Università degli Studi La Sapienza, Roma, Italy. francesca.pagnanelli@uniroma1.it
authors.forename: Francesca
authors.initials: F
authors.lastname: Pagnanelli
authors.forename: Antonio
authors.initials: A
authors.lastname: Esposito
authors.forename: Francesco
authors.initials: F
authors.lastname: Vegliò
mesh_terms: D000327:Adsorption; D018533:Biomass; D006088:Gram-Negative Aerobic Bacteria / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D019216:Metals, Heavy / Q000302:isolation & purification* / Q000378:metabolism*; D008954:Models, Biological; D018508:Water Purification / Q000379:methods*
chemical_list: D019216:Metals, Heavy