Chitosan/silica composite membrane: adsorption of lead(II) Ion from aqueous solution

Abstract

Chitosan membrane has the potential to separate lead(II) ions from aqueous solution. However, the kind of membrane has a drawback due to the low structural properties. Thus, this study investigates the role of silica in improving chitosan-based flat sheet membrane for removal of lead(II) ions from aqueous solution. The functional groups and structural morphologies were characterized using Fourier Transform Infrared-Attenuated Total Reflectance (FTIR-ATR) spectrometer and Scanning Electron Microscope (SEM), respectively. The membrane performance in terms of adsorption study was conducted at different pHs and initial concentration of lead(II) solution. The FTIR-ATR spectrum showed the existence of new absorption peak of chitosan/silica membrane. SEM images revealted the presence of microvoids on the cross-section of the chitosan/silica membrane whereas pure chitosan membrane possessed dense structure. The adsorption study showed that the composite membrane exhibited higher efficiency of lead(II) removal at optimum pH of 7.0 which was 89.27% as compared to 11.50% of pure chitosan membrane. The amount of lead(II) adsorbed onto the membrane was 57.60 mg/g. Therefore, it indicates the potential use of silica to improve the properties of chitosan membrane for removal of heavy metal from water solution.