Modelling and Kinetics of Cd(II) Biosorption onto Inactive Instant Dry Baker's Yeast

This study presents the modeling and kinetics of Cd(II) biosorption from synthetic aqueous solutions onto inactive instant dry baker's yeast Saccharomyces cerevisiae. The biosorption equilibrium was studied by using Langmuir, Freundlich, Dubinin-Radushkevich and Temkin isotherm models. Based on the isotherm parameters and correlation coefficients (R-2) values, we could estimate that Cd(II) biosorption equilibrium was accurately described by Lang-muir model. The maximum monolayer adsorption capacity (Q(m)) determined from the intercept of the linearized Langmuir model was 50 mg g(-1). Cd(II) biosorption onto the inactive instant dry baker's yeast biomass well fitted the pseudo second-order kinetic model. The value of the adsorption energy (E < 16 kJ mol(-1)) and the kinetics results suggested that COD biosorption by the inactive instant dry baker's yeast biomass involved both, electrostatic and chemical interactions.