title: Removal of oxyfluorfen from ex-situ soil washing fluids using electrolysis with diamond anodes.
abstract: In this research, firstly, the treatment of soil spiked with oxyfluorfen was studied using a surfactant-aided soil-washing (SASW) process. After that, the electrochemical treatment of the washing liquid using boron doped diamond (BDD) anodes was performed. Results clearly demonstrate that SASW is a very efficient approach in the treatment of soil, removing the pesticide completely by using dosages below 5 g of sodium dodecyl sulfate (SDS) per Kg of soil. After that, complete mineralization of organic matter (oxyflourfen, SDS and by-products) was attained (100% of total organic carbon and chemical oxygen demand removals) when the washing liquids were electrolyzed using BDD anodes, but the removal rate depends on the size of the particles in solution. Electrolysis of soil washing fluids occurs via the reduction in size of micelles until their complete depletion. Lower concentrations of intermediates are produced (sulfate, chlorine, 4-(trifluoromethyl)-phenol and ortho-nitrophenol) during BDD-electrolyzes. Finally, it is important to indicate that, sulfate (coming from SDS) and chlorine (coming from oxyfluorfen) ions play an important role during the electrochemical organic matter removal.
authors: Institute of Chemistry, Federal University of Rio Grande do Norte, Lagoa Nova CEP 59078-970, Natal, RN, Brazil.
authors: Elisama Vieira
authors: EV
authors: Dos Santos
authors: Department of Chemical Engineering, Universidad de Castilla - La Mancha, Enrique Costa Building, Campus Universitario s/n, 13071, Ciudad Real, Spain.
authors: Cristina
authors: C
authors: Sáez
authors: Institute of Chemistry, Federal University of Rio Grande do Norte, Lagoa Nova CEP 59078-970, Natal, RN, Brazil. Electronic address: carlosmh@quimica.ufrn.br.
authors: Carlos Alberto
authors: CA
authors: Martínez-Huitle
authors: Department of Chemical Engineering, Universidad de Castilla - La Mancha, Enrique Costa Building, Campus Universitario s/n, 13071, Ciudad Real, Spain.
authors: Pablo
authors: P
authors: Cañizares
authors: Department of Chemical Engineering, Universidad de Castilla - La Mancha, Enrique Costa Building, Campus Universitario s/n, 13071, Ciudad Real, Spain.
authors: Manuel Andres
authors: MA
authors: Rodrigo
mesh_terms: D057919:Biological Oxygen Demand Analysis; D001895:Boron / Q000737:chemistry; D018130:Diamond / Q000737:chemistry; D004566:Electrodes; D004572:Electrolysis / Q000379:methods*; D055768:Halogenated Diphenyl Ethers / Q000302:isolation & purification*; D010084:Oxidation-Reduction; D012967:Sodium Dodecyl Sulfate / Q000737:chemistry; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000302:isolation & purification*; D013501:Surface-Active Agents / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*; D018508:Water Purification / Q000379:methods*
chemical_list: D055768:Halogenated Diphenyl Ethers; D012987:Soil; D012989:Soil Pollutants; D013501:Surface-Active Agents; D014874:Water Pollutants, Chemical; D012967:Sodium Dodecyl Sulfate; C016027:oxyfluorofen; D018130:Diamond; D001895:Boron
keywords: Boron doped diamond; Electrolysis; Oxyfluorfen; Soil remediation; Soil washing