Uptake of copper ions from aqueous solutions by Bacillus strain isolated from desert soil

Abstract

Biosorption of copper (Cu) ions from aqueous solutions has been studied in a batch system using a Bacillus species AEJ-89 isolated from Maranjab desert soil. The optimum conditions of biosorption were determined by investigating the initial pH, contact time, and the initial concentrations of metal ions at constant temperature (25°C). The maximum biosorption of Cu ions was observed at pH 5.0 ± 0.1. Biosorption equilibrium times for Cu (II) ions were observed in 30 min. The maximum biosorption capacities of Cu (II) ions on Bacillus species AEJ-89 were determined to be 0.48 mmol g−1 at 200 mg l−1 concentration. The experimental adsorption data were fitted to Langmuir isotherm model. The interactions between metal ions and functional groups on the cell wall surface of the biomass were confirmed by Fourier transform infrared spectroscopy analysis. Cu (II) ions were removed from metal-laden biomass after desorption treatments by the addition of different desorbing solutions. The results indicated that the bacterial isolate Bacillus species AEJ-89 is a suitable biosorbent for the removal of Cu (II) ions from aqueous solutions.