title: Removal of herbicidal ionic liquids by electrochemical advanced oxidation processes combined with biological treatment.
abstract: Recently a new group of ionic liquids (ILs) with herbicidal properties has been proposed for use in agriculture. Owing to the design of specific physicochemical properties, this group, referred to as herbicidal ionic liquids (HILs), allows for reducing herbicide field doses. Several ILs comprising phenoxy herbicides as anions and quaternary ammonium cations have been synthesized and tested under greenhouse and field conditions. However, since they are to be introduced into the environment, appropriate treatment technologies should be developed in order to ensure their proper removal and avoid possible contamination. In this study, didecyldimethylammonium (4-chloro-2-methylphenoxy) acetate was selected as a model HIL to evaluate the efficiency of a hybrid treatment method. Electrochemical oxidation or electro-Fenton was considered as a pretreatment step, whereas biodegradation was selected as the secondary treatment method. Both processes were carried out in current mode, at 10 mA with carbon felt as working electrode. The efficiency of degradation, oxidation and mineralization was evaluated after 6 h. Both processes decreased the total organic carbon and chemical oxygen demand (COD) values and increased the biochemical oxygen demand (BOD5) on the COD ratio to a value close to 0.4, showing that the electrolyzed solutions can be considered as 'readily biodegradable.'
authors.affiliation: a Poznan University of Technology, Institute of Chemistry and Technical Electrochemistry , Poznan , Poland.
authors.forename: Daria
authors.initials: D
authors.lastname: Pęziak-Kowalska
authors.affiliation: b Université Rennes 1/Ecole Nationale Supérieure de Chimie de Rennes, CNRS, UMR 6226 , Rennes , France.
authors.forename: Florence
authors.initials: F
authors.lastname: Fourcade
authors.affiliation: c Poznan University of Technology, Institute of Chemical Technology and Engineering , Poznan , Poland.
authors.forename: Michał
authors.initials: M
authors.lastname: Niemczak
authors.affiliation: b Université Rennes 1/Ecole Nationale Supérieure de Chimie de Rennes, CNRS, UMR 6226 , Rennes , France.
authors.forename: Abdeltif
authors.initials: A
authors.lastname: Amrane
authors.affiliation: c Poznan University of Technology, Institute of Chemical Technology and Engineering , Poznan , Poland.
authors.forename: Łukasz
authors.initials: Ł
authors.lastname: Chrzanowski
authors.affiliation: a Poznan University of Technology, Institute of Chemistry and Technical Electrochemistry , Poznan , Poland.
authors.forename: Grzegorz
authors.initials: G
authors.lastname: Lota
mesh_terms: D000085:Acetates / Q000737:chemistry; D055664:Electrochemical Techniques; D052918:Environmental Restoration and Remediation / Q000379:methods*; D006540:Herbicides / Q000737:chemistry*; D006861:Hydrogen Peroxide / Q000737:chemistry; D052578:Ionic Liquids / Q000737:chemistry*; D010084:Oxidation-Reduction; D000644:Quaternary Ammonium Compounds / Q000737:chemistry; D014865:Waste Disposal, Fluid / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: D000085:Acetates; D006540:Herbicides; D052578:Ionic Liquids; D000644:Quaternary Ammonium Compounds; D014874:Water Pollutants, Chemical; D006861:Hydrogen Peroxide; C027118:didecyldimethylammonium
keywords: Herbicidal ionic liquids; biodegradability; electro-Fenton; electrochemical oxidation