title: Chromium removal using resin supported nanoscale zero-valent iron.
abstract: Resin supported nanoscale zero-valent iron (R-nZVI) was synthesized by the borohydride reduction method. Batch experiments were conducted to evaluate the factors affecting Cr(VI) removal. It was found that nZVI loads, resin dose, pH value and initial concentration of Cr(VI) were all important factors. Scanning electron microscopy showed that the nZVI particles in R-nZVI became sphere after reacting with Cr(VI). This phenomenon was attributed to the co-precipitation of Cr(III) and Fe(III) on the surface of resin. X-ray diffraction pattern confirmed that Fe(0) diminished after the reaction. At optimum conditions, the Cr(VI) removal efficiency was 84.4% when the initial concentration of Cr(VI) was 20.0 mg/L. Regeneration of R-nZVI and resin was possible. R-nZVI can also remove Cr(III) efficiently. However, the removal mechanisms of Cr(VI) (anion) and Cr(III) (cation) are different. The former is chemical reduction, while the latter is ion exchange at pH below 6.3 and precipitation at pH above 6.3. This study demonstrates that R-nZVI has the potential to become an effective agent for treating wastewater containing Cr(VI) and Cr(III).
authors.affiliation: School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, PR China. fufenglian2006@163.com
authors.forename: Fenglian
authors.initials: F
authors.lastname: Fu
authors.forename: Jun
authors.initials: J
authors.lastname: Ma
authors.forename: Liping
authors.initials: L
authors.lastname: Xie
authors.forename: Bing
authors.initials: B
authors.lastname: Tang
authors.forename: Weijiang
authors.initials: W
authors.lastname: Han
authors.forename: Suya
authors.initials: S
authors.lastname: Lin
mesh_terms: D002411:Cation Exchange Resins / Q000737:chemistry; D002857:Chromium / Q000302:isolation & purification*; D006863:Hydrogen-Ion Concentration; D007501:Iron / Q000737:chemistry*; D007700:Kinetics; D053768:Metal Nanoparticles; D008855:Microscopy, Electron, Scanning; D059027:Recycling; D014865:Waste Disposal, Fluid / Q000379:methods; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*; D014961:X-Ray Diffraction
chemical_list: D002411:Cation Exchange Resins; D014874:Water Pollutants, Chemical; D002857:Chromium; D007501:Iron
keywords: Chromium removal; Cr(VI) wastewater; Nanoscale zero-valent iron (nZVI); Resin; Support