Sorptive flotation for metal ions recovery

In this study, the abstraction of nickel, copper and zinc ions from aqueous solutions has been investigated in a laboratory batch scale mode. A combined two-stage process is proposed as an alternative of the heavy metals removal from aqueous solutions. The first stage is the sorption of heavy metals onto non-living microorganisms followed by dispersed-air flotation of the loaded biomass. Three types of strains were used: Penicillium chrysogenum, Saccharomyces carlsbergensis and Streptomyces rimosus. The main parameters studied were solution pH, biomass concentration, surfactant concentration and flocculant concentration. The biomass reuse after elution was also examined. Remediation is a possible application of flotation being cost-effective and with readily available equipment and know-how. The application of this process looks promising. (C) 2003 Elsevier Science B.V. All rights reserved.