A Dynamic Study of the Adsorption of Bentonite-Enriched Sands to Some Toxic Elements

(Lead and Copper)

Abstract

    The study addressed methods for purifying and removing heavy metals, namely lead and copper, as they are the most toxic elements. A unique type of bentonite was obtained from a quarry near the Al-Marqab Cement Factory in the Al-Khums region. The batch extraction method was used, where 2.0 g of bentonite was taken at a constant pH and time to obtain the best experimental conditions for removing heavy elements. Sand samples were also analyzed, and the silica content was 95%. This is a cheap and suitable material for removing contaminated heavy elements, as it is available in Libya. The removal efficiency and Kd (distribution rate) of the heavy elements were then calculated. It became clear that the best conditions were at pH = 5, and that the time factor did not play a significant role. The removal of the lead ion ranged from 64.70% to 91.08% for the bentonite sample, and the removal of the copper ion ranged from 60.64% to 91.96% under the same conditions. The best results studied for pH values ​​at pH = 5 were 98.72% for the lead ion and 94.60% for the copper ion at the same pH. Time had no effective effect on the adsorption process and on the removal of the heavy ion from the solution.