Abstract:
Heavy metals contamination from industrial wastewaters into the environment is a serious environmental problem. Activated carbon adsorption is the most effective means of removing heavy metals from industrial effluents before discharge into the environment but is expensive. Several low cost adsorbents have been utilized as alternatives for heavy metal removal. However a thorough literature search revealed a dart of information on the use of Gourd Cell Seed Husk (GCSH) as adsorbent for heavy metals. This study therefore investigates the performance of GCSH for the biosorption of Co (II), Zn (II) and Pb (II) ions from aqueous solution. The adsorbent was characterized by the Fourier Transform Infrared (FTIR) spectroscopy and Scanning Electron Microscopy (SEM). Batch biosorption was used to determine the effect of pH, metal ion concentration, adsorbent dose and contact time on metals sequestration. Isotherm was analyzed by the Langmuir, Freundlich, Tempkin and Dubinin-Radushkevich models. Kinetic mechanism of biosorption was analyzed using the Pseudo-first order, Pseudo-second order, Intra-particle diffusion and Film diffusion rate equations. FTIR and SEM showed the presence of surface functional groups and a porous surface of GCSH. The trend of metal biosorption was Co (II)>Pb (II)>Zn (II) ions. The results of this study revealed a good performance of GCSH for the removal of the three metal ions from solution. This indicated the usefulness of GCSH as an alternative low cost adsorbent.
