TY - JOUR
T1 - Lead removal from solution by a porous ceramisite made from bentonite, metallic iron, and activated carbon
AU - YUAN, Li
AU - ZHI, Wei
AU - XIE, Qinglong
AU - CHEN, Xi
AU - LIU, Yangsheng
N1 - We acknowledge the two anonymous reviewers for their thorough, insightful, and constructive comments that have significantly improved the paper. This work was supported by the National Natural Science Foundation of China (no. 21077002 and 41201532). Li Yuan acknowledges support from the China Scholarship Council (CSC) visiting scholarship.
PY - 2015/11/1
Y1 - 2015/11/1
N2 - There is increasing interest in using a porous ceramisite as the filter medium for removing heavy metals from wastewater in 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), and activated carbon (AC) were used to prepare a Fe0/AC-ceramisite (diameter 2-4 mm) by sintering at 800 °C in a N2 environment. The Fe0/AC-ceramisite achieved a high Pb2+ removal efficiency (>99%) at ceramisite dosages of 5-10 g L-1, an initial solution pH of 3.0-5.7, and initial Pb2+ concentrations of 50-200 mg L-1. Compared with three control ceramisites including B-ceramisite (made by bentonite only), AC-ceramisite (made by bentonite and AC), and Fe0-ceramisite (made by bentonite and Fe0), the enhanced Pb2+ removal by the Fe0/AC-ceramisite was mainly attributed to the iron-carbon micro-electrolysis induced by the addition of AC. A first-order kinetics model fit well for the Pb2+ removal by the Fe0/AC-ceramisite, and the Pb2+ uptake rate increased linearly with the increasing initial solution pH. Results from scanning electron microscopy equipped with energy dispersive X-ray spectroscopy (SEM/EDX), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) indicated that the Pb2+ removal by the Fe0/AC-ceramisite involved multiple mechanisms including sorption, reduction (from Pb2+ to Pb0), and precipitation (in the forms of PbCO3 and Pb3(CO3)2(OH)2). © 2016 The Royal Society of Chemistry.
AB - There is increasing interest in using a porous ceramisite as the filter medium for removing heavy metals from wastewater in 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), and activated carbon (AC) were used to prepare a Fe0/AC-ceramisite (diameter 2-4 mm) by sintering at 800 °C in a N2 environment. The Fe0/AC-ceramisite achieved a high Pb2+ removal efficiency (>99%) at ceramisite dosages of 5-10 g L-1, an initial solution pH of 3.0-5.7, and initial Pb2+ concentrations of 50-200 mg L-1. Compared with three control ceramisites including B-ceramisite (made by bentonite only), AC-ceramisite (made by bentonite and AC), and Fe0-ceramisite (made by bentonite and Fe0), the enhanced Pb2+ removal by the Fe0/AC-ceramisite was mainly attributed to the iron-carbon micro-electrolysis induced by the addition of AC. A first-order kinetics model fit well for the Pb2+ removal by the Fe0/AC-ceramisite, and the Pb2+ uptake rate increased linearly with the increasing initial solution pH. Results from scanning electron microscopy equipped with energy dispersive X-ray spectroscopy (SEM/EDX), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) indicated that the Pb2+ removal by the Fe0/AC-ceramisite involved multiple mechanisms including sorption, reduction (from Pb2+ to Pb0), and precipitation (in the forms of PbCO3 and Pb3(CO3)2(OH)2). © 2016 The Royal Society of Chemistry.
UR - http://www.scopus.com/inward/record.url?scp=84985011753&partnerID=8YFLogxK
U2 - 10.1039/c5ew00091b
DO - 10.1039/c5ew00091b
M3 - Journal Article (refereed)
SN - 2053-1400
VL - 1
SP - 814
EP - 822
JO - Environmental Science: Water Research and Technology
JF - Environmental Science: Water Research and Technology
IS - 6
ER -