Removal of metal ions from simulated wastewater by Saccharomyces yeast biomass: Combining biosorption and flotation processes

Aqueous solutions containing heavy metals can be successfully treated by a combination Of biosorption and flotation, in order to remove (or recover) t he contained metals. Nonliving biomass of yeast Saccharomyces, which is a s olid industrial by-product, was found to be a suitable biosorbent of metal ions (zinc, copper, and nickel). It was found also possible to reuse it aft er the appropriate desorption treatment. Electrokinetic behavior of biomass as well as elution and multiple-cycles operation were investigated. The di spersed-air flotation technique, which was selected for generation of bubbl es, was subsequently examined for solid/liquid separation, In order to hart est the metals-loaded biomass downstream. The main parameters affecting th e flotation process were studied, Such as the solution pH, the concentratio n of notation collector (surfactant), the preliminary biomass modification, and the biomass concentration: The biosorptive flotation method was found promising for remediation applications of wastewaters containing toxic meta ls.