Elimination of Chromium (VI) and Cadmium(II) from Aqueous Solutions by Adsorption onto Olive Stones
Karima Rouibah1, 2, Abdeslam-Hassen Meniai*, 1, Mohamed Tahar Rouibah2, Lazhar Deffous2, Mossaab Bencheikh Lehocine1
Identifiers and Pagination:Year: 2009
First Page: 41
Last Page: 48
Publisher Id: TOCENGJ-3-41
Article History:Received Date: 13/05/2009
Revision Received Date: 07/08/2009
Acceptance Date: 07/09/2009
Electronic publication date: 21/10/2009
Collection year: 2009
open-access license: This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International Public License (CC-BY 4.0), a copy of which is available at: https://creativecommons.org/licenses/by/4.0/legalcode. This license permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
The present study concerns the test of olive stones as an adsorbent for removing Cd(II) and Cr(VI) from aqueous solutions. The experimental elimination of the two cations was carried out batchwise and the influence of certain physico-chemical parameters such as the contact time, the pH of the solution, the temperature, the solid to liquid ratio, the agitation speed were also considered. The equilibrium adsorption capacity of the olive stones for the case of Cr(VI) followed the Langmuir model, whereas for the Cd(II) cations, the two models i.e. Langmuir and Freundlich were equally representative. The adsorption process was found to be of pseudo second order and the rate constants were determined for both cations. The Gibbs free energy sign was negative for the adsorption of both cations, indicating that the process was spontaneous. Finally the olive stones retained chromium more than cadmium, but at optimal conditions, high removal percentages were reached, for both cations.