title: Adsorption and desorption of uranium (VI) in aerated zone soil.
abstract: In this paper, the adsorption and desorption behavior of uranium (VI) in aerated zone soil (from Southwest China) was systematically investigated using a static experimental method in order to provide useful information for safety assessment of the disposal of (ultra-)low uraniferous radioactive waste, as well as a potential remediation method for uranium-contaminated soils. The adsorption behavior of uranium (VI) was firstly studied by batch experiments as functions of contact time, pH, liquid/solid ratio, temperature, colloids, minerals and coexistent ions. The results indicated that the adsorption of uranium (VI) by natural soil was efficient at an initial concentration of 10 mg/L uranium (VI) nitrate solution with 100 mg natural soil at room temperature when pH is about 7.0. The adsorption was strongly influenced by the solution pH, contact time, initial concentration and colloids. The adsorption equilibrium for uranium (VI) in soil was obtained within 24 h and the process could be described by the Langmuir adsorption equation. For uranium (VI) desorption, EDTA, citric acid and HNO(3) were evaluated under different conditions of temperature, concentration and proportion of liquid to solid. The adsorbed uranium (VI) on natural soil could be easily extracted by all these agents, especially by HNO(3), implying that the uranium-contaminated soils can be remedied by these reagents.
authors.affiliation: Key Laboratory of Radiation Physics and Technology, Ministry of Education, Institute of Nuclear Science and Technology, Sichuan University, Chengdu 610064, PR China.
authors.forename: Xiaolong
authors.initials: X
authors.lastname: Li
authors.forename: Jiaojiao
authors.initials: J
authors.lastname: Wu
authors.forename: Jiali
authors.initials: J
authors.lastname: Liao
authors.forename: Dong
authors.initials: D
authors.lastname: Zhang
authors.forename: Jijun
authors.initials: J
authors.lastname: Yang
authors.forename: Yue
authors.initials: Y
authors.lastname: Feng
authors.forename: Junhui
authors.initials: J
authors.lastname: Zeng
authors.forename: Wei
authors.initials: W
authors.lastname: Wen
authors.forename: Yuanyou
authors.initials: Y
authors.lastname: Yang
authors.forename: Jun
authors.initials: J
authors.lastname: Tang
authors.forename: Ning
authors.initials: N
authors.lastname: Liu
mesh_terms: D000327:Adsorption; D001578:Benzopyrans / Q000737:chemistry; D002614:Chelating Agents / Q000737:chemistry; D019343:Citric Acid / Q000737:chemistry; D004492:Edetic Acid / Q000737:chemistry; D006812:Humic Substances; D006863:Hydrogen-Ion Concentration; D008903:Minerals / Q000032:analysis; D017942:Nitric Acid / Q000737:chemistry; D012987:Soil / Q000032:analysis; D012990:Soil Pollutants, Radioactive / Q000737:chemistry*; D013696:Temperature; D014501:Uranium / Q000737:chemistry*
chemical_list: D001578:Benzopyrans; D002614:Chelating Agents; D006812:Humic Substances; D008903:Minerals; D012987:Soil; D012990:Soil Pollutants, Radioactive; D019343:Citric Acid; D017942:Nitric Acid; D014501:Uranium; D004492:Edetic Acid; C005023:fulvic acid