SUSPENDED AND IMMOBILIZED BREWERY WASTE BIOMASS AND COMMERCIAL YEAST AS BIOSORBENTS FOR Cd(II) REMOVAL. A THERMODYNAMIC STUDY

Bioremediation of heavy metals pollution remains a major challenge in environmental biotechnology. This paper presents the potential of yeast collected from two sources, used in two forms (commercial yeast and brewery waste biomass, in suspended and immobilized forms) for cadmium ions biosorption from synthetic monocomponent solution. Thermodynamic parameters, including Gibbs free energy (Delta G degrees), enthalpy (Delta H degrees) and entropy (Delta S degrees) of adsorption were calculated. The obtained results showed that the biosorption of Cd(II) onto Saccharomyces cerevisiae strain was a feasible, spontaneous and endothermic process in nature. Between the four tested biosorbents, the best efficiency and adsorption capacity was determined for the brewery waste biomass, which could be successfully used as an alternative low-cost biosorbent.