title: Activation of Manganese Oxidants with Bisulfite for Enhanced Oxidation of Organic Contaminants: The Involvement of Mn(III).
abstract: MnO4(-) was activated by HSO3(-), resulting in a process that oxidizes organic contaminants at extraordinarily high rates. The permanganate/bisulfite (PM/BS) process oxidized phenol, ciprofloxacin, and methyl blue at pHini 5.0 with rates (kobs ≈ 60-150 s(-1)) that were 5-6 orders of magnitude faster than those measured for permanganate alone, and ∼5 to 7 orders of magnitude faster than conventional advanced oxidation processes for water treatment. Oxidation of phenol was fastest at pH 4.0, but still effective at pH 7.0, and only slightly slower when performed in tap water. A smaller, but still considerable (∼3 orders of magnitude) increase in oxidation rates of methyl blue was observed with MnO2 activated by HSO3(-) (MO/BS). The above results, time-resolved spectroscopy of manganese species under various conditions, stoichiometric analysis of pH changes, and the effect of pyrophosphate on UV absorbance spectra suggest that the reactive intermediate(s) responsible for the extremely rapid oxidation of organic contaminants in the PM/BS process involve manganese(III) species with minimal stabilization by complexation. The PM/BS process may lead to a new category of advanced oxidation technologies based on contaminant oxidation by reactive manganese(III) species, rather than hydroxyl and sulfate radicals.
authors.affiliation: State Key Laboratory of Pollution Control and Resources Reuse, Tongji University , Shanghai 20092, People's Republic of China.|State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology , Harbin 150090, People's Republic of China.
authors.forename: Bo
authors.initials: B
authors.lastname: Sun
authors.affiliation: State Key Laboratory of Pollution Control and Resources Reuse, Tongji University , Shanghai 20092, People's Republic of China.
authors.forename: Xiaohong
authors.initials: X
authors.lastname: Guan
authors.affiliation: School of Environmental Science and Engineering, Sun Yat-Sen University , Guangzhou 510275, People's Republic of China.
authors.forename: Jingyun
authors.initials: J
authors.lastname: Fang
authors.affiliation: Institute of Environmental Health, Oregon Health & Science University , 3181 SW Sam Jackson Park Road, Portland, Oregon 97239-3098, United States.
authors.forename: Paul G
authors.initials: PG
authors.lastname: Tratnyek
mesh_terms: D001557:Benzenesulfonates / Q000737:chemistry; D002939:Ciprofloxacin / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D017665:Hydroxyl Radical; D008345:Manganese / Q000737:chemistry*; D017895:Manganese Compounds / Q000737:chemistry*; D016877:Oxidants / Q000737:chemistry*; D010084:Oxidation-Reduction; D010087:Oxides / Q000737:chemistry*; D010636:Phenols / Q000737:chemistry; D013056:Spectrophotometry, Ultraviolet; D013447:Sulfites / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000737:chemistry*; D018508:Water Purification / Q000379:methods*
chemical_list: D001557:Benzenesulfonates; D017895:Manganese Compounds; D016877:Oxidants; D010087:Oxides; D010636:Phenols; D013447:Sulfites; D014874:Water Pollutants, Chemical; C048856:permanganic acid; D017665:Hydroxyl Radical; D008345:Manganese; D002939:Ciprofloxacin; C414357:Methyl Blue; C042345:hydrogen sulfite