Heavy metals removal from solution by palygorskite clay
- 31 August 2005
- journal article
- Published by Elsevier BV in Minerals Engineering
- Vol. 19 (5), 463-470
- https://doi.org/10.1016/j.mineng.2005.07.004
Abstract
The possible use of palygorskite clay, mined in the Dwaalboom area of the Northern Province of South Africa, as an adsorbent for the removal of metal ions such as lead, nickel, chromium and copper from aqueous solution, was investigated. In this work, adsorption of these metals onto palygorskite has been studied by using a batch method at room temperature. The results of adsorption were fitted to both the Langmuir and Freundlich models. Satisfactory agreement between experimental data and the model-predicted values was expressed by the correlation coefficient (R2). The Langmuir model represented the sorption process better than the Freundlich one, with correlation coefficient (R2) values ranging from 0.953 to 0.994. The adsorption capacity (Q0) calculated from the Langmuir isotherm was 62.1 mg Pb(II) g−1, 33.4 mg Ni(II) g−1, 58.5 mg Cr(VI) g−1 and 30.7 mg Cu(II) g−1 at a pH of 7.0 at 25 ± 1 °C for a clay particle size of 125 μm. Kinetic investigations were performed to investigate the rate of adsorption of metal ions. The Lagergren’s first-order rate constants were calculated for different initial concentrations of metal ions. In batch mode adsorption studies, removal increased with an increase of contact time, adsorbent amount and solution pH. Adsorption of metals from the single-metal solutions was in the order: Pb > Cr > Ni > Cu. Data from this study proved that metal cations from aqueous solution can be adsorbed successfully in significant amounts by palygorskite. This opens up new possibilities and potential commercial uses in the palygorskite market.Keywords
This publication has 14 references indexed in Scilit:
- Batch adsorptive removal of copper ions in aqueous solutions by ion exchange resins: 1200H and IRN97HKorean Journal of Chemical Engineering, 2004
- An evaluation of copper biosorption by a brown seaweed under optimized conditionsElectronic Journal of Biotechnology, 2003
- Sorption equilibria of metal ions on bone charChemosphere, 2003
- Adsorption of Cu Ions onto a 1.10 Phenanthroline-Grafted Brazilian BentoniteClays and Clay Minerals, 2003
- Selective adsorption of chromium(VI) in industrial wastewater using low-cost abundantly available adsorbentsAdvances in Environmental Research, 2002
- Comparative study of adsorption properties of Turkish fly ashesJournal of Hazardous Materials, 2002
- Removal of Ni(II) from aqueous solution by adsorption onto hazelnut shell activated carbon: equilibrium studiesBioresource Technology, 2002
- Removal of Pb(II) from aqueous/acidic solutions by using bentonite as an adsorbentWater Research, 2001
- Adsorption of nickel(II) from aqueous solution onto activated carbon prepared from coirpithSeparation and Purification Technology, 2001
- Adsorption of chromium (VI) by a low-cost adsorbent: Biogas residual slurryChemosphere, 1995