Removal of As(III) and As(V) from aqueous solutions using nanoscale zero valent iron-reduced graphite oxide modified composites.
Nanoscale zero valent iron (NZVI) has high adsorption capacity of As(III) and As(V), but it is limited in practical use due to its small particle size and aggregation effect. Reduce graphite oxide (RGO) has been used as a support because of its high surface area. In order to utilize the advantage of NZVI and RGO as well as to avoid the disadvantage of NZVI, we loaded NZVI onto RGO via chemical reactions in this study. The adsorption capacity of As(III) and As(V), as determined from the Langmuir adsorption isotherms in batch experiments, was 35.83mgg(-1) and 29.04mgg(-1), respectively. And the adsorption kinetics fitted well with pseudo-second-order model. The residual concentration was found to meet the standard of WHO after the samples were treated with 0.4gL(-1) NZVI-RGO when the initial concentration of As(III) and As(V) were below 8ppm and 3ppm. Especially, when the initial concentration of As(III) was below 3ppm, the residual concentration was within 1ppb; whereas, the residual concentration was undetected when the initial concentration of As(III) was 1ppm.
College of Environment and Energy, South China University of Technology, Guangzhou 510006, China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, Guangzhou 510006, China.
Can
C
Wang
College of Environment and Energy, South China University of Technology, Guangzhou 510006, China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, Guangzhou 510006, China. Electronic address: luohj@scut.edu.cn.
Hanjin
H
Luo
College of Environment and Energy, South China University of Technology, Guangzhou 510006, China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, Guangzhou 510006, China.
Zilong
Z
Zhang
College of Environment and Energy, South China University of Technology, Guangzhou 510006, China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, Guangzhou 510006, China.
Yan
Y
Wu
College of Environment and Energy, South China University of Technology, Guangzhou 510006, China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, Guangzhou 510006, China.
Jian
J
Zhang
College of Environment and Energy, South China University of Technology, Guangzhou 510006, China; Department of Chemistry and Biochemistry, University of California, Santa Cruz, CA 95064 USA.
Shaowei
S
Chen
D000327:Adsorption; D001149:Arsenates / Q000302:isolation & purification*; D018053:Arsenites / Q000302:isolation & purification*; D006108:Graphite / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007501:Iron / Q000737:chemistry*; D007700:Kinetics; D046529:Microscopy, Electron, Transmission; D008956:Models, Chemical; D053758:Nanoparticles / Q000737:chemistry*; D012996:Solutions; D013499:Surface Properties; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*; D014961:X-Ray Diffraction
D001149:Arsenates; D018053:Arsenites; D012996:Solutions; D014874:Water Pollutants, Chemical; D006108:Graphite; D007501:Iron
Arsenic removal; Characteration; Nanoscale zero valent iron; Reduced graphite oxide