title: Fe(II)-Al(III) layered double hydroxides prepared by ultrasound-assisted co-precipitation method for the reduction of bromate.
abstract: Bromate is recognized as an oxyhalide disinfection byproduct in drinking water. In this paper, Fe(II)-Al(III) layered double hydroxides (Fe-Al LDHs) prepared by the ultrasound-assisted co-precipitation method were used for the reduction of bromate in solution. The Fe-Al LDHs particles were characterized by X-ray diffractometer, scanning electron microscopy and thermogravimetry-differential scanning calorimetry. It was found that ultrasound irradiation assistance promoted the formation of the hydrotalcite-like phase and then improved the removal efficiency of bromate. In addition, the effects of solid-to-solution ratio, contact time, initial bromate concentration, initial pH, coexisting anions on the bromate removal were investigated. The results showed the bromate with an initial concentration of 1.56 μmol/L could be completely removed from solution by Fe-Al LDHs within 120 min. When the initial bromate concentration was 7.81 μmol/L, the Fe-Al LDHs with irradiation time of 30 min exhibited the optimum removal efficiency and the bromate removal capacity (qe) was 6.80 μmol/g. In addition, the appearance of sulfate and production of bromide were observed simultaneously in this process, which suggested that ion-exchange between sulfate and bromate, and the reduction of bromate to bromide by Fe(2+) were the main mechanisms responsible for the bromate removal by Fe-Al LDHs.
authors.affiliation: College of Environmental Science and Engineering, Hunan University, Changsha 410082, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Zhong
authors.forename: Qi
authors.initials: Q
authors.lastname: Yang
authors.forename: Kun
authors.initials: K
authors.lastname: Luo
authors.forename: Xiuqiong
authors.initials: X
authors.lastname: Wu
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Li
authors.forename: Yang
authors.initials: Y
authors.lastname: Liu
authors.forename: Wangwang
authors.initials: W
authors.lastname: Tang
authors.forename: Guangming
authors.initials: G
authors.lastname: Zeng
authors.forename: Bo
authors.initials: B
authors.lastname: Peng
mesh_terms: D000535:Aluminum / Q000737:chemistry*; D000838:Anions; D001959:Bromates / Q000737:chemistry*; D002152:Calorimetry, Differential Scanning; D002852:Chromatography, Ion Exchange; D006863:Hydrogen-Ion Concentration; D006878:Hydroxides / Q000737:chemistry*; D007501:Iron / Q000737:chemistry*; D007700:Kinetics; D008855:Microscopy, Electron, Scanning; D013431:Sulfates / Q000737:chemistry; D013818:Thermogravimetry / Q000379:methods; D014465:Ultrasonics; D014867:Water / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000302:isolation & purification*; D018508:Water Purification / Q000379:methods*; D014881:Water Supply; D014961:X-Ray Diffraction
chemical_list: D000838:Anions; D001959:Bromates; D006878:Hydroxides; D013431:Sulfates; D014874:Water Pollutants, Chemical; D014867:Water; D000535:Aluminum; D007501:Iron