Experimental investigation of activated carbon prepared from date stones adsorbent electrode for electrosorption of lead from aqueous solution

The objective of this study is the removal of lead from aqueous solution by electrosorption on carbon prepared from lignocellulosic natural residue date stones. The electrosorption efficiency was evaluated after the thermally treatment of the raw material at 900 degrees C. Adsorption of lead from aqueous solution by activated carbon electrodes was investigated through electrosorption experiments by changing potentials from +/- 0.05 to +/- 0.5 V/SCE. The results allow to observe that the application of a negative potential (-0,13 V) increases the adsorption capacity until 17.71 mg/g, while a positive potential (+0,13 V) released lead from the activated carbon up to 17.02 mg/g, showing the reversibility of the sorption process. The effect of pH and cycles number on the elestosorption process was studied. The experimental results concluded that the better adsorption efficiency (97.5%) was obtained when pH is 5. Furthermore, it was confirmed that the recycling process of adsorption/desorption could be conducted for seven adsorption-desorption cycles.