Abstract:Biosorption of Au(III) from tetrabromoauric acid with eggshell membrane was studied to investigate effects of particle size of biomass, pH value, and contact time on adsorption. Eggshell membrane before and after adsorption was characterize by FESEM, FT-IR and XRD. Adsorption kinetics and thermodynamic equation were investigated. The results show that the optimum pH value for Au(III) adsorption is six, and particle size of eggshell membrane within 0.297~0.115 mm has no effect on adsorption. Biosorption of Au(III) is resulted from interaction of physical adsorption and chemical adsorption, and chemical adsorption plays a major role. The biggest adsorbing capacity at 25 ℃ is 438.6 mg/g. Au(III) biosorption better ?ts Langmuir model and pseudo-second-order kinetic model.