الفهرس | Only 14 pages are availabe for public view |
Abstract The objective of this study is to investigate the efficiency of using drinking water treatment sludge (DWTS), light white brick (LWBW) and red brick (HOMRA) wastes as solid adsorbents for the removal of heavy metal ions like lead, cadmium and nickel from their aqueous solution. The physicochemical characteristics of each solid waste were investigated using X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscopy (SEM) and N2 adsorption-desorption isotherms. Besides, the effect of different parameters such as contact time, initial pH, initial metal ion concentrations, adsorbent dose and competition of metal ions on the adsorption of heavy metal ions was studied by using batch experiments. In addition, the effect of firing temperatures on the removal efficiency of these heavy metal ions from their solutions was investigated in case of DWTS. The removal efficiency at optimum conditions was approximately 100% for Pb+2, Cd+2 and Ni+2 using DWTS and LWBW and 100, 20 and 9.7%, respectively using HOMRA. The adsorption kinetics of ions was followed the pseudo-second-order model based on the amounts of metal sorbed at various time intervals. Keywords: Solid waste, heavy metals, wastewater, sludge, brick waste, low cost adsorbent. |