Comparative study of selected heavy metals removal from aqueous solution by using carbonized sunflower seeds husks and imine Ligands

Abstract

Heavy metal pollution is currently one of the most important environmental threats in the world. Because of their recalcitrance and persistence in the environment, the treatment of heavy metals is filled with difficulties. Several technologies for removing heavy the later analytes from wastewater have been developed in recent years. Adsorption is a very good solution for the removal of heavy metals from industrial effluent and other polluted streams, among all classic and current approaches. Various cheap plant materials can also be used as adsorbents to make the adsorption process more economical. This study was performed to evaluate the ability of carbonized sunflower seed husks and synthetized imine ligands to remove Cu (II), Pb (II) cations from wastewater. Both artificial and natural wastewaters through batch adsorption were used in this study. Sunflower seed husks have been cleaned to remove dirt before drying and then carbonized in the oven at 300°C. Next, carbonized peels were ground and sieved to a size less than 0.3mm and directly used in different adsorbent/metal ion ratios. Imine ligands were also synthetized [Tris(((di(pyridin-2-yl) methylene) amino) methyl) amine(L1), 1,1-di(pyridin-2-yl)-N-(pyridin-2-ylmethyl) methanimine (L2) and the product between Trisaminoethylamine and salicylaldehyde (L5)]. On the percentage of heavy metal removal, the effects of contact time, initial metal concentration, loading weight of adsorbent, and pH were examined. Optimum values obtained are (pH5.5, 15mg/l of initial metal concentration, 6g/L of adsorbent dose, and 1hour contact time by using carbonized sunflower husks as adsorbent) and kept constant in the following experiments. The removal percentage observed was 68% by CSH,43% by L1, 67% by L2, 65% by L5 for Pb (II) ions, and 58% by CSH, 39% by L1, 65% by L2, 71% for Cu (II) ions. From the analysis, it was found that Carbonized sunflower seeds husks successfully removed heavy metals almost at the same level with imine ligands. Therefore, Sunflower seeds husks that are eco-friendly and cost-effective materials, can be utilized as adsorbents to successfully remove metal ions from aqueous solutions.