Table of Contents
ISRN Environmental Chemistry
Volume 2014, Article ID 705069, 10 pages
Research Article

Effect of Physical and Chemical Activation on the Removal of Hexavalent Chromium Ions Using Palm Tree Branches

Surface Chemistry and Catalysis Laboratory, National Research Center, El-Dokki, Cairo 12622, Egypt

Received 23 February 2014; Accepted 13 March 2014; Published 2 April 2014

Academic Editors: D. Petruzzelli and C. Waterlot

Copyright © 2014 Soheir Khedr et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Nowadays the removal of heavy metals from wastewater is essential due to their high toxicity and impact on human health. In the present study, branches of palm trees were converted into activated carbon by chemical and physical activation. The prepared samples were used for the removal of Cr(VI) from their aqueous solution. Chemical activation was carried out using (20 and 50%) H3PO4 and K2CO3, and physical activation was performed using steam. Batch adsorption experiments were carried out to examine the removal process under factors such as pH and . The metal ion removal was pH dependent and reached maximum removal at pH 2. Experimental data were analyzed using Langmuir, Freundlich, and Flory-Huggins isotherms. The adsorption studies revealed that the removal of Cr(VI) ions was well fitted with Langmuir isotherm. The adsorption kinetics well fitted using a pseudo second-order kinetic model. Column studies revealed that the highest bed volume (60 BV) was observed for the sample activated with 50% H3PO4. The adsorption efficiency was enhanced with acid treatment (50% H3PO4) and reduced by steam.