WASTE MICROBIAL BIOMASS FOR CADMIUM ION REMOVAL - APPLICATION OF FLOTATION FOR DOWNSTREAM SEPARATION

The uses of microorganisms, including live and dead bacterial biomass such as the actinomycetes, have been widely studied. In the present wo rk flotation is proposed as the separation stage for harvesting suspen ded micro-organisms following biosorption of cadmium. The parameters i nvestigated in batch mode were solution pH, ionic strength, use of a f rother (ethanol) and a cationic collector (cetyl trimethylammonium bro mide) and biomass elution by EDTA. The process was also compared with cadmium ion flotation. Promising results were obtained with dead Strep tomyces biomass in dilute aqueous cadmium solutions.