corn cob, biosorption, heavy metals, characterization, desorption
Abstract
The objective of this study was to investigate corncob as biosorbent for heavy metals removal from aqueous solutions. All biosorption experiments were performed in batch system. The biosorbent were caracterized by thermal analysis (DTA/TGA), Scanning Electron Microscopy and Energy Disperzive X-Ray analysis (SEM-EDX) and Fourier Transform Infrared Spectroscopy (FTIR) analysis. FTIR analysis of corn cob before and after Pb2+, Cu2+ and Zn2+ removal from aqueous solutions showed that ion exchange and chemisorption were involved in biosorption process of metal ions on to corn cob. Experimental data were fitted by Langmuir and Freundlich isotherm models. Maximum adsorption capacity of corn cob for Pb2+, Cu2+ and Zn2+ were 5,59; 2,62 i 1,23 mg/g, respectively. Desorption study showed that metal adsorbed corn cob can be effectively regenerated by HNO3 solution. Results from this study indicated that corn cob can be used as potential biosorbent for Pb2+, Cu2+ and Zn2+ removal from aqueous solutions.