Authors: Ali Sdiri; Teruo Higashi; Tamao Hatta; Fakher Jamoussi; Norio Tase
Addresses: Graduate School of Life and Environmental Science, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Ibaraki 305-8572, Japan. ' Graduate School of Life and Environmental Science, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Ibaraki 305-8572, Japan. ' Japan International Research Center for Agricultural Sciences, Ohwashi 1-1, Tsukuba, 305-8686, Japan. ' Centre National de Recherches en Sciences des Matériaux (CNRSM), Technopôle Borj Cédria, BP 273, 8020 Soliman, Tunisia. ' Graduate School of Life and Environmental Science, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Ibaraki 305-8572, Japan
Abstract: This study focused on the removal of Pb(II), Cd(II), Cu(II), and Zn(II) using reagent solutions by natural limestone in a batch system. The sorbent, collected from the Late Cretaceous limestone beds, Tunisia, was characterised by X-ray diffraction (XRD), chemical analysis (XRF) and infrared spectroscopy (FTIR). XRF showed that the studied limestone contained high amount of calcium carbonates. XRD confirmed the presence of quartz along with the sharp peaks of calcite. FTIR spectra indicated that limestone was mainly composed of calcite, confirming the results of XRD and XRF analyses. Preliminary adsorption tests indicated that high removal efficiency could be achieved by limestone. The presence of impurities enhanced the adsorption capacity. Kinetic experiments showed that the sorption of metal ions best fitted the second order kinetic model with equilibration time of 60 min. These results suggested that the Campanian-Maastritchian limestone could be used for the removal of toxic metals from wastewaters.
Keywords: Campanian-Maastritchtian limestone; heavy metals; sorption; environmental conservation; heavy metal removal; aqueous solutions; water quality; water pollution; lead removal; copper removal; cadmium removal; zinc removal; reagent solutions; Tunisia; quartz; calcite; wastewater treatment; adsorption capacity; kinetic modelling.
International Journal of Global Environmental Issues, 2012 Vol.12 No.2/3/4, pp.171 - 178
Received: 29 Dec 2010
Accepted: 26 Mar 2011
Published online: 02 Oct 2012 *