title: Rapid acceleration of ferrous iron/peroxymonosulfate oxidation of organic pollutants by promoting Fe(III)/Fe(II) cycle with hydroxylamine.
abstract: The reaction between ferrous iron (Fe(II)) with peroxymonosulfate (PMS) generates reactive oxidants capable of degrading refractory organic contaminants. However, the slow transformation from ferric iron (Fe(III)) back to Fe(II) limits its widespread application. Here, we added hydroxylamine (HA), a common reducing agent, into Fe(II)/PMS process to accelerate the transformation from Fe(III) to Fe(II). With benzoic acid (BA) as probe compound, the addition of HA into Fe(II)/PMS process accelerated the degradation of BA rapidly in the pH range of 2.0-6.0 by accelerating the key reactions, including the redox cycle of Fe(III)/Fe(II) and the generation of reactive oxidants. Both sulfate radicals and hydroxyl radicals were considered as the primary reactive oxidants for the degradation of BA in HA/Fe(II)/PMS process with the experiments of electron spin resonance and alcohols quenching. Moreover, HA was gradually degraded to N2, N2O, NO2 (−), and NO3 (−), while the environmentally friendly gas of N2 was considered as its major end product in the process. The present study might provide a promising idea based on Fe(II)/PMS process for the rapid degradation of refractory organic contaminants in water treatment.
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology , Harbin 150090, P.R. China.
authors.forename: Jing
authors.initials: J
authors.lastname: Zou
authors.forename: Jun
authors.initials: J
authors.lastname: Ma
authors.forename: Liwei
authors.initials: L
authors.lastname: Chen
authors.forename: Xuchun
authors.initials: X
authors.lastname: Li
authors.forename: Yinghong
authors.initials: Y
authors.lastname: Guan
authors.forename: Pengchao
authors.initials: P
authors.lastname: Xie
authors.forename: Chao
authors.initials: C
authors.lastname: Pan
mesh_terms: D019817:Benzoic Acid / Q000737:chemistry; D004578:Electron Spin Resonance Spectroscopy; D016166:Free Radical Scavengers / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D019811:Hydroxylamine / Q000737:chemistry*; D007501:Iron / Q000737:chemistry*; D009930:Organic Chemicals / Q000737:chemistry*; D016877:Oxidants / Q000737:chemistry; D010084:Oxidation-Reduction; D010545:Peroxides / Q000737:chemistry*; D013997:Time Factors; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: D016166:Free Radical Scavengers; D009930:Organic Chemicals; D016877:Oxidants; D010545:Peroxides; D014874:Water Pollutants, Chemical; C038288:peroxymonosulfate; D019811:Hydroxylamine; D019817:Benzoic Acid; D007501:Iron