title: Efficiency of several leaching reagents on removal of Cu, Pb, Cd, and Zn from highly contaminated paddy soil.
abstract: The efficiency of five different single leaching reagents (tartaric acid (TA), citric acid (CA), CaCl2, FeCl3, EDTA) and two different composite leaching reagents (CA + FeCl3, CA + EDTA) on removing Cu, Pb, Zn, and Cd from contaminated paddy soil in Hunan Province (in China) was studied. The results indicated that the efficiencies of CA, FeCl3, and EDTA on extracting Cu, Pb, Cd, and Zn from soil were greater than that of TA and CaCl2, and their extraction efficiencies were EDTA ≥ FeCl3> CA. The efficiencies of CA + FeCl3on extracting Cu, Pb, Cd, and Zn were higher than that of single CA or FeCl3. The 25 mmol L-1CA + 20 mmol L-1FeCl3was a promising composite leaching reagent for paddy soil, and it could remove Cu (57.6 %), Pb (59.3 %), Cd (84.8 %), and Zn (28.0 %), respectively. With the same amount of leaching reagent, the efficiency of continuous leaching by several times was higher than that by once. In addition, the easily reducible and oxidizable fractions of heavy metals showed significant decrease during the process of leaching.
authors.affiliation: Key Laboratory of Subtropical Agricultural Resource and Environment, Ministry of Agriculture, College of Resources and Environment, Huazhong Agricultural University, Wuhan, 430070, China.
authors.forename: Ruili
authors.initials: R
authors.lastname: Gao
authors.affiliation: Key Laboratory of Subtropical Agricultural Resource and Environment, Ministry of Agriculture, College of Resources and Environment, Huazhong Agricultural University, Wuhan, 430070, China.
authors.forename: Pengfei
authors.initials: P
authors.lastname: Zhu
authors.affiliation: Key Laboratory of Subtropical Agricultural Resource and Environment, Ministry of Agriculture, College of Resources and Environment, Huazhong Agricultural University, Wuhan, 430070, China.
authors.forename: Guangguang
authors.initials: G
authors.lastname: Guo
authors.affiliation: Key Laboratory of Subtropical Agricultural Resource and Environment, Ministry of Agriculture, College of Resources and Environment, Huazhong Agricultural University, Wuhan, 430070, China.
authors.forename: Hongqing
authors.initials: H
authors.lastname: Hu
authors.affiliation: Key Laboratory of Subtropical Agricultural Resource and Environment, Ministry of Agriculture, College of Resources and Environment, Huazhong Agricultural University, Wuhan, 430070, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Zhu
authors.affiliation: Key Laboratory of Subtropical Agricultural Resource and Environment, Ministry of Agriculture, College of Resources and Environment, Huazhong Agricultural University, Wuhan, 430070, China. fuqingling@mail.hzau.edu.cn.
authors.forename: Qingling
authors.initials: Q
authors.lastname: Fu
mesh_terms: D019343:Citric Acid / Q000737:chemistry; D004787:Environmental Pollution; D019216:Metals, Heavy / Q000302:isolation & purification*; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000302:isolation & purification*
chemical_list: D019216:Metals, Heavy; D012987:Soil; D012989:Soil Pollutants; D019343:Citric Acid
keywords: Chemical speciation; Composite leaching; Heavy metal; Paddy soil; Remediation