Competitive sorption of Pb(II), Cu(II) and Ni(II) on carbonaceous nanofibers: A spectroscopic and modeling approach.
The competitive sorption of Pb(II), Cu(II) and Ni(II) on the uniform carbonaceous nanofibers (CNFs) was investigated in binary/ternary-metal systems. The pH-dependent sorption of Pb(II), Cu(II) and Ni(II) on CNFs was independent of ionic strength, indicating that inner-sphere surface complexation dominated sorption Pb(II), Cu(II) and Ni(II) on CNFs. The maximum sorption capacities of Pb(II), Cu(II) and Ni(II) on CNFs in single-metal systems at a pH 5.5±0.2 and 25±1°C were 3.84 (795.65mg/g), 3.21 (204.00mg/g) and 2.67 (156.70mg/g)mmol/g, respectively. In equimolar binary/ternary-metal systems, Pb(II) exhibited greater inhibition of the sorption of Cu(II) and Ni(II), demonstrating the stronger affinity of CNFs for Pb(II). The competitive sorption of heavy metals in ternary-metal systems was predicted quite well by surface complexation modeling derived from single-metal data. According to FTIR, XPS and EXAFS analyses, Pb(II), Cu(II) and Ni(II) were specifically adsorbed on CNFs via covalent bonding. These observations should provide an essential start in simultaneous removal of multiple heavy metals from aquatic environments by CNFs, and open the doorways for the application of CNFs.
School of Environment and Chemical Engineering, North China Electric Power University, Beijing 102206, PR China; Key Lab of New Thin Film Solar Cells, Institute of Plasma Physics, Chinese Academy of Science, P.O. Box 1126, Hefei 230031, PR China; University of Science and Technology of China, Hefei 230032, PR China.
Congcong
C
Ding
School of Environment and Chemical Engineering, North China Electric Power University, Beijing 102206, PR China; Key Lab of New Thin Film Solar Cells, Institute of Plasma Physics, Chinese Academy of Science, P.O. Box 1126, Hefei 230031, PR China; University of Science and Technology of China, Hefei 230032, PR China.
Wencai
W
Cheng
School of Environment and Chemical Engineering, North China Electric Power University, Beijing 102206, PR China; Key Lab of New Thin Film Solar Cells, Institute of Plasma Physics, Chinese Academy of Science, P.O. Box 1126, Hefei 230031, PR China; University of Science and Technology of China, Hefei 230032, PR China.
Xiangxue
X
Wang
Division of Nanomaterials and Chemistry, Hefei National Laboratory for Physical Science at Microscale, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, PR China.
Zhen-Yu
ZY
Wu
Key Lab of New Thin Film Solar Cells, Institute of Plasma Physics, Chinese Academy of Science, P.O. Box 1126, Hefei 230031, PR China. Electronic address: sunyb@ipp.ac.cn.
Yubing
Y
Sun
Key Lab of New Thin Film Solar Cells, Institute of Plasma Physics, Chinese Academy of Science, P.O. Box 1126, Hefei 230031, PR China.
Changlun
C
Chen
School of Environment and Chemical Engineering, North China Electric Power University, Beijing 102206, PR China; Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions and School for Radiological and Interdisciplinary Sciences, Soochow University, 215123 Suzhou, PR China; NAAM Research Group, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia. Electronic address: xkwang@ncepu.edu.cn.
Xiangke
X
Wang
Division of Nanomaterials and Chemistry, Hefei National Laboratory for Physical Science at Microscale, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, PR China.
Shu-Hong
SH
Yu
Carbonaceous nanofibers; Competitive sorption; EXAFS analysis; Heavy metals; Surface complexation modeling