title: Phenol abatement using persulfate activated by nZVI, H2O2and NaOH and development of a kinetic model for alkaline activation.
abstract: Three persulfate (PS) activation methods (nanoparticles of zero-valent iron (nZVI), hydrogen peroxide and alkali) were compared using phenol as target pollutant. Firstly, four experiments were conducted at 25°C in a batch way using the same initial phenol and oxidant concentrations (10 mM and 420 mM, respectively), being the molar ratio activator/PS fixed to 0.005 with nZVI (mass ratio 0.0011 nZVI/PS), to 2 using hydrogen peroxide and to 2 and 4 with NaOH. Phenol and PS conversions and aromatic byproducts profiles during 168 h reaction time were measured and compared, as well as mineralization and ecotoxicity of the samples. It was found that both phenol and aromatic byproducts (catechol and hydroquinone) totally disappeared using PS activated by alkali before 24 h, while a significant amount of aromatic intermediates was obtained with nZVI and H2O2. Additional runs were carried out using shorter times (0-2 h) to discriminate the oxidation route and the kinetic model of phenol abatement by using PS activated by alkali. Different initial concentrations of phenol (5-15 mM), PS (210 and 420 mM) and molar ratio NaOH/PS (2 and 4) were employed. The kinetic model obtained predicts accurately the evolution of phenol, persulfate, hydroquinone and catechol.
authors.affiliation: a Dpto. Ingeniería Química, Facultad CC, Químicas , Universidad Complutense de Madrid , Madrid , Spain.
authors.forename: Miguel A
authors.identifier: http://orcid.org/0000-0002-2827-7066
authors.initials: MA
authors.lastname: Lominchar
authors.affiliation: a Dpto. Ingeniería Química, Facultad CC, Químicas , Universidad Complutense de Madrid , Madrid , Spain.
authors.forename: Sergio
authors.initials: S
authors.lastname: Rodríguez
authors.affiliation: a Dpto. Ingeniería Química, Facultad CC, Químicas , Universidad Complutense de Madrid , Madrid , Spain.
authors.forename: David
authors.initials: D
authors.lastname: Lorenzo
authors.affiliation: a Dpto. Ingeniería Química, Facultad CC, Químicas , Universidad Complutense de Madrid , Madrid , Spain.
authors.forename: Noelia
authors.initials: N
authors.lastname: Santos
authors.affiliation: a Dpto. Ingeniería Química, Facultad CC, Químicas , Universidad Complutense de Madrid , Madrid , Spain.
authors.forename: Arturo
authors.initials: A
authors.lastname: Romero
authors.affiliation: a Dpto. Ingeniería Química, Facultad CC, Químicas , Universidad Complutense de Madrid , Madrid , Spain.
authors.forename: Aurora
authors.initials: A
authors.lastname: Santos
mesh_terms: D006861:Hydrogen Peroxide; D007501:Iron; D007700:Kinetics; D008956:Models, Chemical; D053758:Nanoparticles / Q000737:chemistry*; D010084:Oxidation-Reduction; D019800:Phenol / Q000737:chemistry*; D012972:Sodium Hydroxide / Q000737:chemistry*; D013431:Sulfates / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: D013431:Sulfates; D014874:Water Pollutants, Chemical; D019800:Phenol; D012972:Sodium Hydroxide; D006861:Hydrogen Peroxide; D007501:Iron
keywords: Activated persulfate; alkali activation; byproducts; kinetic model; phenol