Evaluation of Adsorption and Desorption Properties of PAA-PSBF for Cd(II) from Aqueous Solution

Abstract

In this study, a poly(acrylic acid)-modified polysulfone-Escherichia coli biomass composite fiber (PAA-PSBF) was used for the removal of Cd(II) from aqueous solution. FT-IR analysis confirmed that PAA was successfully modified on the PSBF surface. The adsorption and desorption properties of PAA-PSBF for Cd(II) were evaluated through pH edge, adsorption kinetic, adsorption isotherm, and desorption experiments. The pH edge experiments were carried out at initial Cd(II) concentrations of 50 and 100 mg/L, in the pH range of 2-7. The results showed that the optimal pH for Cd(II) removal was 7. The adsorption kinetic experiments confirmed that the adsorption equilibrium at pH 7 requires at least 240 min. The isotherm experimental data were well fitted by the Langmuir model, and the maximum Cd(II) uptake on PAA-PSBF was calculated as 47.39 mg/g. In addition, the reusability study revealed that the adsorption capacity of PAA-PSBF for Cd(II) was only slightly decreased while its desorption efficiency remained at above 93.88 %.