Abstract

This study aimed to investigate some heavy metal removal using waste biomass adsorbent persimmon leaves in an aqueous solution. Persimmon leaves, which are biomaterials, have many hydroxyl groups and are highly suitable for removing heavy metals. Therefore, in this study, we investigated the possibility of removing Al, Fe, Pb, and Cd in an aqueous solution using dried persimmon leaves (DPL). Some factors which affected the removal were studied, such as the effect of drying temperature, the quantity of adsorbent, pH, the effect of initial metal ions concentration, the effect of contact time, impact of foreign ion interference, while the best drying temperature was (150,150,105,105 C°) for Al, Fe, Pb, Cd respectively. Furthermore, the best quantity of adsorbent was (1,0.25,0.5,0.5 g) for Al, Fe, Pb, and Cd, respectively. The suitable initial metal ions concentration was 2 mg/L for Al, Fe, Pb, and Cd, respectively. The order of removal efficiency was found to be Fe >Pb> Cd>Al. In another method, some of the DPL was converted to nano powder which was used to investigate the removal of Pb and Cd from aqueous solutions. The nano DPL is more active than the normal DPL. Normal DPL was applied to two samples first one was a sewage water sample, and the other sample was groundwater. The pseudo-second-order model was better suited for the heavy metal adsorption experiments using DPL than the pseudo-first-order model. The adsorption of Al, Fe, Pb, and Cd by DPL was more suitable with the Freundlich isothermal adsorption. It showed an ion exchange reaction in the uneven adsorption surface, indicating that the heavy metal adsorption on DPL was easy. The affinity of heavy metal adsorption to DPL was excellent. This experiment, in which heavy metals are removed using the waste biomass of persimmon leaves, is an eco-friendly bio-adsorbent method because it can remove heavy metals without using chemicals while utilizing waste recycling.