title: Application of zero-valent iron nanoparticles for the removal of aqueous zinc ions under various experimental conditions.
abstract: Application of zero-valent iron nanoparticles (nZVI) for Zn²⁺ removal and its mechanism were discussed. It demonstrated that the uptake of Zn²⁺ by nZVI was efficient. With the solids concentration of 1 g/L nZVI, more than 85% of Zn²⁺ could be removed within 2 h. The pH value and dissolved oxygen (DO) were the important factors of Zn²⁺ removal by nZVI. The DO enhanced the removal efficiency of Zn²⁺. Under the oxygen-contained condition, oxygen corrosion gave the nZVI surface a shell of iron (oxy)hydroxide, which could show high adsorption affinity. The removal efficiency of Zn²⁺ increased with the increasing of the pH. Acidic condition reduced the removal efficiency of Zn²⁺ by nZVI because the existing H⁺ inhibited the formation of iron (oxy)hydroxide. Adsorption and co-precipitation were the most likely mechanism of Zn²⁺ removal by nZVI. The FeOOH-shell could enhance the adsorption efficiency of nZVI. The removal efficiency and selectivity of nZVI particles for Zn²⁺ were higher than Cd²⁺. Furthermore, a continuous flow reactor for engineering application of nZVI was designed and exhibited high removal efficiency for Zn²⁺.
authors.affiliation: State Key Laboratory of Pollution Control and Resources Reuse, Tongji University, Shanghai, China.
authors.forename: Wen
authors.initials: W
authors.lastname: Liang
authors.affiliation: State Key Laboratory of Pollution Control and Resources Reuse, Tongji University, Shanghai, China ; College of Civil Engineering, Tongji University, Shanghai, China.
authors.forename: Chaomeng
authors.initials: C
authors.lastname: Dai
authors.affiliation: State Key Laboratory of Pollution Control and Resources Reuse, Tongji University, Shanghai, China.
authors.forename: Xuefei
authors.initials: X
authors.lastname: Zhou
authors.affiliation: State Key Laboratory of Pollution Control and Resources Reuse, Tongji University, Shanghai, China.
authors.forename: Yalei
authors.initials: Y
authors.lastname: Zhang
mesh_terms: D002104:Cadmium / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D007477:Ions; D007501:Iron / Q000737:chemistry*; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D010084:Oxidation-Reduction; D010100:Oxygen / Q000737:chemistry; D056951:Photoelectron Spectroscopy; D012212:Rheology; D012996:Solutions; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*; D014961:X-Ray Diffraction; D015032:Zinc / Q000302:isolation & purification*
chemical_list: D007477:Ions; D012996:Solutions; D014874:Water Pollutants, Chemical; D002104:Cadmium; D007501:Iron; D015032:Zinc; D010100:Oxygen