title: Effect of precursor concentration on the characteristics of nanoscale zerovalent iron and its reactivity of nitrate.
abstract: Differing precursor concentrations, 1.0, 0.1, and 0.01 M FeCl(3) x 6H(2)O, were performed to produce nanoscale Fe(0) and the results were discussed in terms of the specific surface area, particle size and electrochemical properties. The results indicated that the nanoscale Fe(0) prepared by 0.01 M FeCl(3) had absolutely reduced in size (9-10nm) and possessed the greatest specific surface area (56.67 m(2) g(-1)). These synthesized nanoscale Fe(0) particles were attempted to enhance the removal of 40 mg-NL(-1) unbuffered nitrate solution. The first-order degradation rate constants (k(obs)) increased significantly (5.5-8.6 times) with nanoscale Fe(0) prepared by 0.01 M precursor solution (Fe(0.01 M)(0)). When normalized to iron surface area concentration, the specific rate constant (k(SA)) was increased by a factor of approximately 1.7-2.4 using Fe(0.01 M)(0) (6.84 x 10(-4) L min(-1) m(-2) for Fe(0.01 M)(0), 4.04 x 10(-4) L min(-1) m(-2) for Fe(0.1 M)(0) and 2.80 x 10(-4) L min(-1) m(-2) for Fe(1 M)(0)). The rise of reactivity of the reactive site on the Fe(0.01 M)(0) surface was indicated by the specific rate constant (k(SA)) calculation and the i(0) value of the electrochemical test.
authors.affiliation: Research Center for Environmental Pollution Prevention and Control Technology, Graduate Institute of Environmental Engineering, National Taiwan University, Taipei 106, Taiwan.
authors.forename: Ya Hsuan
authors.initials: YH
authors.lastname: Liou
authors.forename: Shang-Lien
authors.initials: SL
authors.lastname: Lo
authors.forename: Wen Hui
authors.initials: WH
authors.lastname: Kuan
authors.forename: Chin-Jung
authors.initials: CJ
authors.lastname: Lin
authors.forename: Shih Chi
authors.initials: SC
authors.lastname: Weng
mesh_terms: D007501:Iron / Q000737:chemistry / Q000494:pharmacology*; D046529:Microscopy, Electron, Transmission / Q000379:methods; D036103:Nanotechnology / Q000379:methods; D009566:Nitrates / Q000378:metabolism*; D010084:Oxidation-Reduction; D014873:Water Pollutants / Q000378:metabolism; D018508:Water Purification / Q000379:methods*
chemical_list: D009566:Nitrates; D014873:Water Pollutants; D007501:Iron