Removal of Hg(II) from Aqueous Solution by Bacillus subtilis ATCC 6051 (B1)

Abstract

Hg (II) has been as one of the most toxic metals on health hazards. The biosorption of toxic metals from aqueous solution by biomass is effective as an alternative method in recent years. Therefore, the biosorption of Hg(II) was examined in view of solution pH, initial concentration of Hg(II), contact time and reaction temperature by using Bacillus subtilis ATCC 6051(B1). Concentration of Hg (II) was measured by ICP-MS. FT-IR was employed for the characterization of bacterial surface. pH of 4.5 was found as the best acidity of aqueous samples. The results from kinetic studies suggested that Hg(II) bio adsorption was best represented by the pseudo second order equation. Results from equilibrium data fitted to Langmuir isotherm model. While ΔH° and ΔS° was obtained as 76.01 kJ/mol and 239, 11 kJ/mol respectively, ΔG° had a low value (4.76 kJ/mol). This study demonstrated that Bacillus subtilis having low cost can be used as an effective biosorbent for Hg(II) removal from aqueous solutions.