title: Fe/Al bimetallic particles for the fast and highly efficient removal of Cr(VI) over a wide pH range: Performance and mechanism.
abstract: The iron/aluminum (Fe/Al) bimetallic particles with high efficiency for the removal of Cr(VI) were prepared. Fe/Al bimetallic particles were characterized by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), SEM mapping, X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). SEM mapping showed that the core of bimetal was Al, and the planting Fe was deposited on the surface of Al. In acidic and neutral conditions, Fe/Al bimetal can completely remove Cr(VI) from wastewater in 20 min. Even at pH 11.0, the Cr(VI) removal efficiency achieved was 93.5%. Galvanic cell effect and high specific surface area are the main reasons for the enhanced removal of Cr(VI) by bimetallic particles. There were no iron ions released in solutions at pH values ranging from 3.0 to 11.0. The released Al(3+) ions concentrations in acidic and neutral conditions were all less than 0.2mg/L. The bimetal can be used 4 times without losing activity at initial pH 3.0. XPS indicated that the removed Cr(VI) was immobilized via the formation of Cr(III) hydroxide and Cr(III)-Fe(III) hydroxide/oxyhydroxide on the surface of Fe/Al bimetal. The Fe/Al bimetallic particles are promising for further testing for the rapid and effective removal of contaminants from water.
authors.affiliation: School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, PR China; Environmental Engineering and Science Program, Department of Biomedical, Chemical and Environmental Engineering (DBCEE), University of Cincinnati, OH 45221-0012, USA. Electronic address: fufenglian2006@163.com.
authors.forename: Fenglian
authors.initials: F
authors.lastname: Fu
authors.affiliation: School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, PR China.
authors.forename: Zihang
authors.initials: Z
authors.lastname: Cheng
authors.affiliation: Environmental Engineering and Science Program, Department of Biomedical, Chemical and Environmental Engineering (DBCEE), University of Cincinnati, OH 45221-0012, USA. Electronic address: dionysios.d.dionysiou@uc.edu.
authors.forename: Dionysios D
authors.initials: DD
authors.lastname: Dionysiou
authors.affiliation: School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, PR China.
authors.forename: Bing
authors.initials: B
authors.lastname: Tang
mesh_terms: D000535:Aluminum / Q000737:chemistry*; D002857:Chromium / Q000302:isolation & purification*; D004572:Electrolysis; D006863:Hydrogen-Ion Concentration; D007501:Iron / Q000737:chemistry*; D053758:Nanoparticles; D010316:Particle Size; D014865:Waste Disposal, Fluid / Q000379:methods; D062065:Wastewater; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*; D018508:Water Purification / Q000379:methods
chemical_list: D000535:Aluminum; D002857:Chromium; D007501:Iron; D062065:Wastewater; D014874:Water Pollutants, Chemical; C074702:chromium hexavalent ion
keywords: Cr(VI) wastewater; Fe/Al bimetallic particles; Reaction mechanism; Removal