title: Facile functionalized of SBA-15 via a biomimetic coating and its application in efficient removal of uranium ions from aqueous solution.
abstract: A novel dopamine-functionalized mesoporous silica (DMS), synthesized by grafting dopamine onto a mesoporous molecular sieve (SBA-15), was developed as a sorbent to extract U(VI) from aqueous solution. The method used to modify SBA-15 was simple, facile and cost-effective. The DMS was characterized by SEM, TEM, XRD and BET, showing that the material had an ordered mesoporous structure and a large surface area. The effect of contact time, pH, ionic strength, temperature, and solid-liquid ratio on the sorption process was investigated. It was demonstrated that the adsorption of U(VI) by DMS was fast and that it can be described by the pseudo-second order-equation where the equilibrium time was 20 min. Additionally, the adsorption isotherm data were fitted well by the Langmuir model with the maximum adsorption capacity of DMS of 196 mg/g at pH 6.0. Furthermore, the influence of the K(+) and Na(+) concentrations and solid-to-liquid ratio on the sorption was very weak, and the values of the thermodynamic parameters revealed that the sorption process was exothermic and spontaneous. All the results suggested that the DMS could be used as an excellent adsorbent to remove U(VI) from aqueous solution.
authors.affiliation: School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China; School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, China.
authors.forename: Jun-Kai
authors.initials: JK
authors.lastname: Gao
authors.affiliation: School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China.
authors.forename: Li-An
authors.initials: LA
authors.lastname: Hou
authors.affiliation: School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China.
authors.forename: Guang-Hui
authors.initials: GH
authors.lastname: Zhang
authors.affiliation: School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China. Electronic address: guping@tju.edu.cn.
authors.forename: Ping
authors.initials: P
authors.lastname: Gu
mesh_terms: D000327:Adsorption; D040761:Biomimetic Materials / Q000737:chemistry*; D004298:Dopamine / Q000737:chemistry*; D007700:Kinetics; D008956:Models, Chemical; D015394:Molecular Structure; D012822:Silicon Dioxide / Q000737:chemistry*; D012996:Solutions; D013499:Surface Properties; D013816:Thermodynamics; D014501:Uranium / Q000302:isolation & purification*; D014875:Water Pollutants, Radioactive / Q000302:isolation & purification*; D018508:Water Purification / Q000379:methods*
chemical_list: C509969:SBA-15; D012996:Solutions; D014875:Water Pollutants, Radioactive; D014501:Uranium; D012822:Silicon Dioxide; D004298:Dopamine
keywords: Adsorption; Biomimetic coating; Dopamine; Mesoporous material; Uranium