title: A study of the reaction of ferrate with pentachlorophenol - kinetics and degradation products.
abstract: Pentachlorophenol (PCP) is a persistent pollutant which has been widely used as a pesticide and a wood preservative. As PCP is toxic and is present in significant quantities in the environment, there is considerable interest in elimination of PCP from waters. One of the promising methods is the application of ferrate. Ferrate is an oxidant and coagulant. It can be applied as a multi-purpose chemical for water and wastewater treatment as it degrades a wide range of environmental pollutants. Moreover, ferrate is considered a green oxidant and disinfectant. This study focuses on the kinetics of PCP degradation by ferrate under different pH conditions. The formation of degradation products is also considered. The second-order rate constants of the PCP reaction with ferrate increased from 23 M-1s-1to 4,948 M-1s-1with a decrease in pH from 9 to 6. At neutral pH the degradation was fast, indicating that ferrate could be used for rapid removal of PCP. The total degradation of PCP was confirmed by comparing the initial PCP molarity with the molarity of chloride ions released. We conclude no harmful products are formed during ferrate treatment as all PCP chlorine was released as chloride. Specifically, no polychlorinated dibenzo-p-dioxins and dibenzofurans were detected.
authors.affiliation: Faculty of Mechatronics, Informatics and Interdisciplinary Studies & the Institute for Nanomaterials, Advanced Technologies and Innovation, Technical University of Liberec, Studentská 1402/2, Liberec 46117, Czech Republic E-mail: martina.homolkova@tul.cz.
authors.forename: M
authors.initials: M
authors.lastname: Homolková
authors.affiliation: Faculty of Mechatronics, Informatics and Interdisciplinary Studies & the Institute for Nanomaterials, Advanced Technologies and Innovation, Technical University of Liberec, Studentská 1402/2, Liberec 46117, Czech Republic E-mail: martina.homolkova@tul.cz.
authors.forename: P
authors.initials: P
authors.lastname: Hrabák
authors.affiliation: Department of Civil and Environmental Engineering, Imperial College London, South Kensington Campus, London SW7 2AZ, UK.
authors.forename: N
authors.initials: N
authors.lastname: Graham
authors.affiliation: Faculty of Mechatronics, Informatics and Interdisciplinary Studies & the Institute for Nanomaterials, Advanced Technologies and Innovation, Technical University of Liberec, Studentská 1402/2, Liberec 46117, Czech Republic E-mail: martina.homolkova@tul.cz.
authors.forename: M
authors.initials: M
authors.lastname: Černík
mesh_terms: D002713:Chlorine; D004785:Environmental Pollutants / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007501:Iron / Q000737:chemistry*; D007700:Kinetics; D016877:Oxidants; D010416:Pentachlorophenol / Q000737:chemistry*; D010575:Pesticides / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: D004785:Environmental Pollutants; D016877:Oxidants; D010575:Pesticides; D014874:Water Pollutants, Chemical; C017311:ferrate ion; D002713:Chlorine; D010416:Pentachlorophenol; D007501:Iron