Abstract
The adsorption characteristics of Pb(II) and Cd(II) onto colemanite ore waste (CW) from aqueous solution were investigated as a function of pH, adsorbent dosage, contact time, and temperature. Langmuir, Freundlich and Dubinin-Radushkevich (D-R) models were applied to describe the adsorption isotherms. Langmuir model fitted the equilibrium data better than the Freundlich isotherm. The adsorption capacity of CW was found to be 33.6 mg/g and 29.7 mg/g for Pb(II) and Cd(II) ions, respectively. Analyte ions were desorbed from CW using both 1 M HCl and 1 M HNO3. The recovery for both metal ions was found to be higher than 95%. The mean adsorption energies evaluated using the D-R model indicated that the adsorption of Pb(II) and Cd(II) onto CW were taken place by chemisorption. The thermodynamic parameters (ΔGo, ΔHo and ΔSo) showed that the adsorption of both metal ions was feasible, spontaneous and exothermic at 20-50 °C. Adsorption mechanisms were also investigated using the pseudo-first-order and pseudo-second-order kinetic models. The kinetic results showed that the adsorption of Pb(II) and Cd(II) onto CW followed well pseudo-second order kinetics.
| Original language | English |
|---|---|
| Pages (from-to) | 260-266 |
| Number of pages | 7 |
| Journal | Desalination |
| Volume | 249 |
| Issue number | 1 |
| DOIs | |
| State | Published - 30 Nov 2009 |
| Externally published | Yes |
Bibliographical note
Funding Information:The authors are grateful for the financial support of the Unit of the Scientific Research Projects of Gaziosmanpasa University . The authors also would like to thank Esra Melek for her helps in experimental studies.
Keywords
- Cd(II)
- Colemanite ore waste (CW)
- Kinetics
- Pb(II)
- Thermodynamics
ASJC Scopus subject areas
- General Chemistry
- General Chemical Engineering
- General Materials Science
- Water Science and Technology
- Mechanical Engineering