Ali Reza Rahmani
1, Maryam Forough
1, Zahra Noorimotlagh
2, Shervin Adabi
1*1 Department of Environmental Health Engineering, School of Health, Hamedan University of Medical Sciences, Hamedan, Iran
2 Environmental Technologies Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
*Corresponding Author: Corresponding author: Shervin Adabi, Hamedan University of Medical Sciences, Hamedan, Iran. Tel: +98-9188745722, Fax: +98-8138380509, Email:
vazanah5@gmail.com
Abstract
Cr (VI) as an extremely soluble and highly toxic ion is present in effluents of industries and imposes severe health-related problems.
The current study aimed to provide information on Cr (VI) adsorption potential of fire clay as an abundant, cost-effective and
untried material. Batch adsorption trials of Cr (VI) were performed to investigate the effects of pH, contact time, initial metal ion
concentration and the adsorbent dosage. Langmuir, Freundlich and Dubinin–Radushkevich isotherm models were used to evaluate
the equilibrium data at 20°C and regression coefficients were derived. Moreover, adsorption kinetics was analyzed using the
pseudo-first-order and the pseudo-second-order kinetic models. Maximum chromium removal was found at pH 2.0. A kinetic study
yielded an optimum equilibrium time of 90 minutes with an adsorbent dose of 2.5 g/50 mL. Results suggested that the equilibrium
adsorption described by the Freundlich model. The kinetic data of the sorption showed that the pseudo second-order equation was
the more appropriate. The results of the study indicated that fire clay was not a suitable adsorbent for Cr (IV). Apart from relatively
long equilibrium time, the efficiency was not satisfactory. Therefore, searching for better alternative and/or modify such adsorbent
is necessary in this area.