TY - JOUR
T1 - Sorption mechanisms of lead on silicon-rich biochar in aqueous solution
T2 - Spectroscopic investigation
AU - Li, Jianhong
AU - Zheng, Lirong
AU - Wang, Shan Li
AU - Wu, Zhipeng
AU - Wu, Weidong
AU - Niazi, Nabeel Khan
AU - Shaheen, Sabry M.
AU - Rinklebe, Jörg
AU - Bolan, Nanthi
AU - Ok, Yong Sik
AU - Wang, Hailong
N1 - Funding Information:
We are indebted to all staff at the 1W1B station for providing us beamtime of the Beijing Synchrotron Radiation Facility at the Institute of High Energy Physics, and beamline 15U1 of Shanghai Synchrotron Radiation Facility, Chinese Academy of Sciences. This work was financially supported by the National Key Research and Development Program of China ( 2018YFD0800703 , 2017YFD0202101 ), the Natural Science Foundation of China ( 21577131 , 21866013 , 21876027 ), Guangdong Provincial Natural Science Foundation , China ( 2017A030311019 ), Hainan Provincial Natural Science Foundation , China (Grant Nos. 317190 and 418QN208 ), the Postgraduate Innovation Project of Hainan Province ( Hyb2017-20 ), the Crop Science Postgraduate Innovation Project of Hainan University Tropical Agriculture and Forestry College ( ZWCX2018013 ), and the Ecology Discipline Construction Funding of Hainan University . Thanks are extended by Professor Sabry M. Shaheen to the Alexander von Humboldt Foundation for the Postdoctoral Research Fellowship (Ref 3.4 - EGY - 1185373 - GF-E) at the University of Wuppertal, Germany.
Publisher Copyright:
© 2019
PY - 2019/7/1
Y1 - 2019/7/1
N2 - Unraveling sorption mechanisms of lead (Pb) to silicon (Si)-rich biochar at molecular scale in aqueous solution are essential for the effective application of the biochars to the remediation of Pb and other metal(loid)s pollution in the environment. Thus, this study investigated the contributions of phytoliths and other compounds to the Pb sorption on Si-rich coconut fiber biochar (CFB500) and the corresponding sorption mechanisms using spectroscopic techniques, including the micro-X-ray fluorescence (μ-XRF), X-ray absorption fine structure (XAFS), scanning electron microscopy combined with energy dispersive X-ray spectroscopy, and X-ray diffraction. The μ-XRF and XAFS results showed that K, Ca, Cu, Mn, and Fe were released and significantly related to Pb in Pb-loaded CFB500; four major Pb species were formed with similar structures to lead carboxylate (e.g., Pb(C 2 H 3 O 2 ) 2 ), Pb 3 (PO 4 ) 2 , PbSiO 3 , and PbCO 3 . On phytoliths in CFB500, Pb 2+ ions were mainly sorbed on the sites of silicate with a structure similar to PbSiO 3 . The contribution of binding sites for Pb 2+ sorption was ascribed to the outer-wall of carbon skeleton of CFB500, which was stronger than that provided by the mineral oxide aggregate and phytoliths on CFB500. Organic carbon functional groups, inorganic carbonates, silicates and phosphates on CFB500 mostly dominated the sorption sites for Pb 2+ . Our results suggest that CFB500 was a promising material for the remediation of Pb-contaminated aqueous environments (e.g., wastewater).
AB - Unraveling sorption mechanisms of lead (Pb) to silicon (Si)-rich biochar at molecular scale in aqueous solution are essential for the effective application of the biochars to the remediation of Pb and other metal(loid)s pollution in the environment. Thus, this study investigated the contributions of phytoliths and other compounds to the Pb sorption on Si-rich coconut fiber biochar (CFB500) and the corresponding sorption mechanisms using spectroscopic techniques, including the micro-X-ray fluorescence (μ-XRF), X-ray absorption fine structure (XAFS), scanning electron microscopy combined with energy dispersive X-ray spectroscopy, and X-ray diffraction. The μ-XRF and XAFS results showed that K, Ca, Cu, Mn, and Fe were released and significantly related to Pb in Pb-loaded CFB500; four major Pb species were formed with similar structures to lead carboxylate (e.g., Pb(C 2 H 3 O 2 ) 2 ), Pb 3 (PO 4 ) 2 , PbSiO 3 , and PbCO 3 . On phytoliths in CFB500, Pb 2+ ions were mainly sorbed on the sites of silicate with a structure similar to PbSiO 3 . The contribution of binding sites for Pb 2+ sorption was ascribed to the outer-wall of carbon skeleton of CFB500, which was stronger than that provided by the mineral oxide aggregate and phytoliths on CFB500. Organic carbon functional groups, inorganic carbonates, silicates and phosphates on CFB500 mostly dominated the sorption sites for Pb 2+ . Our results suggest that CFB500 was a promising material for the remediation of Pb-contaminated aqueous environments (e.g., wastewater).
KW - Phytoliths skeleton
KW - SEM-EDS
KW - Sorption sites
KW - Toxic metal(loid)s
KW - XAFS
KW - μ-XRF
UR - http://www.scopus.com/inward/record.url?scp=85063875119&partnerID=8YFLogxK
U2 - 10.1016/j.scitotenv.2019.04.003
DO - 10.1016/j.scitotenv.2019.04.003
M3 - Article
C2 - 30965268
AN - SCOPUS:85063875119
VL - 672
SP - 572
EP - 582
JO - Science of the Total Environment
JF - Science of the Total Environment
SN - 0048-9697
ER -