Characterization of an novel extracellular biopolymer BC11 by scanning electron microscopy and FT-IR spectroscopy and its use for lead removal

In the present study we reported the feasibility of extracellular biopolymer(BC11) produced by Bacillus cereus as an alternative biosorbent to remove Pb(II) metallic ions from environmental and industrial wastewater. The ability of BC11 to remove the Pb(II) ions was investigated by using batch biosorption procedure. The effects such as pH, dosage of biosorbent, Pb(II) initial concentration and sorbate-sorbent contact time on the adsorption capacities of BC11 were studied. Biosorption equilibriums were rapidly established in about 60 min and the adsorption kinetic data was fitted with second order kinetic model. The equilibrium adsorption data fit well with Langmuir isotherm. The maximum lead adsorption capacity determined from Langmuir isotherm was 87.25 mg/g BC11 at pH 5.0 , at 25°C and shaker speed 150 rpm, respectively. The carboxyl , hydroxyl and amino groups of the BC11 were involved in chemical interaction with the Pb(II) ions depicted by scanning electron microscopic (SEM) and Fourier transform infrared spectroscopic (FTIR) results. The study points to the potential of new use of extracellular biopolymer BC11 as an effective biosorbent for the removal of Pb(II) and from environmental and industrial wastewater.