Aplicação de biomassa fúngica de Pleurotus ostreatus em processo de biossorção de íons cobre (II)

Abstract

The present work aimed to study the kinetics of removal of copper (II) from synthetic aqueous solutions through biosorption using the fungus Pleurotus ostreatus. The fungus was grown in minimal medium, under stirring and used as biosorbent dry. For the determination of optimum conditions of biosorption used an experimental design, 23 factorial with three replications at the central point in batch. The maximum biosorption was determined by kinetic studies. The equilibrium isotherms were fitted to Langmuir and Freundlich models. The Cu (II) were quantified by colorimetric method with reactive neocuproíne. The results showed that the best optimum condition corresponds to the lowest concentration of biosorbent (0,05 g) and longer experiment (8 min), removing 86.01% of copper ions (II) from synthetic aqueous solutions. Among the three variables (pH, biosorbent mass and time) used in the experimental design, the time was the most significant parameter on the process of biosorption. The variation of initial pH did not significantly affect the level of 95%. The kinetic study revealed that in 5 minutes biomass reached 82.63%, 75.45% and 52.46% of its saturation capacity for the initial concentrations of metal ions copper 3, 5 and 10 mg.L-1, respectively. The Langmuir model was the best fit to the experimental data of biosorbent Pleurotus ostreatus. The maximum amount of copper (II) adsorbed by biosorbent was 380.30 mg.g-1.