Lead removal from solution by a porous ceramisite made from bentonite, metallic iron, and activated carbon

摘要: There is increasing interest in using a porous ceramisite as the filter medium for removing heavy metals from wastewater China given its low cost, easy preparation, large available quantities, high mechanical strength, and good performance to remove various pollutants. In this study, bentonite, metallic iron (Fe0), activated carbon (AC) were used prepare Fe0/AC-ceramisite (diameter 2–4 mm) by sintering at 800 °C N2 environment. The achieved Pb2+ removal efficiency (>99%) dosages of 5–10 g L−1, an initial solution pH 3.0–5.7, concentrations 50–200 mg L−1. Compared with three control ceramisites including B-ceramisite (made bentonite only), AC-ceramisite AC), Fe0-ceramisite Fe0), enhanced was mainly attributed iron–carbon micro-electrolysis induced addition AC. A first-order kinetics model fit well Fe0/AC-ceramisite, uptake rate increased linearly pH. Results scanning electron microscopy equipped energy dispersive X-ray spectroscopy (SEM/EDX), diffraction (XRD), photoelectron (XPS) indicated that involved multiple mechanisms sorption, reduction (from Pb0), precipitation (in forms PbCO3 Pb3(CO3)2(OH)2).