Remediation of Pb-contaminated port sediment by biosurfactant from Bacillus sp. G1

The remediation of Pb-contaminated port sediment by biosurfactant from a new isolated Bacillus sp. G1 was studied. The Pb removal efficiencies were investigated under multi-levels of water-solid ratio, pH and ionic strength. Result showed that exchangeable speciation of Pb could be removed by maximum removal capacity of 76.8 mg/g after leaching. The Langmuir isotherm reflected the adsorption process best to fit the experimental adsorption equilibrium data. Fourier transform infrared spectra (FTIR) indicated that C=O and -CH3 may be the functional groups. Scanning electron microscopy (SEM) analysis showed that the surface of the port sediment became much smoother after adsorption interaction, which reflected that the complexation between Pb ions and biosurfactant was more stable. The results indicated that the biosurfactant of Bacillus sp. G1 could remove Pb effectively from the Pb-contaminated port sediment (PCPS) and suggested a novel method for PCPS remediation.