Document Type : Research Paper


1 Department of Chemical Engineering, Faculty of Engineering, University of Kurdistan, Sanandaj, Kurdistan, Iran.

2 Chemical Engineering Faculty, Amirkabir University of Technology, Tehran Polytechnic, Tehran, Iran.

3 Mechanical Engineering Faculty, Sharif University of Technology, Tehran, Iran.



Inexpensive and new adsorbents, which are produced by processing the abundant agricultural by-products, can provide an efficient solution for a cleaner environment. The occurrence of heavy metals in water may pose a significant threat to human health. In this work, the processed date kernels are used to remove chromium (VI) and iron (III) from water. The XRD, FTIR, SEM, VSM and EDX techniques are used to characterize the adsorbents. The equilibrium adsorbent dose for iron is 2 g/L while for chromium (VI) it is 4 g/L and the equilibrium time is 20 min. Moreover, acidic conditions favored the adsorption for both targets. The adsorption experiments showed that the kinetics of adsorption of chromium (VI) and iron (III) on date kernel powder fitted the pseudo-second-order model. The optimum adsorption capacities for iron (III) and chromium (VI) are 10.5 mg/g and 0.66 mg/g, respectively. In the meantime, the remarkable efficiency of the date kernel-based adsorbent for iron (III) removal paves the way for designing new magnetic adsorbents.


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