BACKGROUND: Benzene, toluene, ethylbenzene, xylene (BTEX) and oxy-fuels such as methyl tert-butyl ether (MTBE) are typical contaminants of ground waters. Biological and physical techniques are often ineffective in removing these compounds, while promising results were obtained with advanced oxidation processes (AOPs), which are based on oxidation by hydroxyl radicals. Electrochemical oxidation with boron doped diamond (BDD) anodes occurs by OH radicals generated from water oxidation, so that it may be considered as an alternative to other AOPs. RESULTS: An experimental study on the electrochemical removal of MTBE and BTEX with BDD anodes from water with low organic concentrations and low conductivity is presented. The kinetics of the process was investigated by batch electrolyses: the removal of MTBE and benzene was controlled by the mass transfer towards the anode, while a further reaction bulk contribution was found for alkylbenzenes. The process was tested in continuous mode and the energy consumption was evaluated and compared with other AOPs. CONCLUSIONS: Removal of the pollutants higher than 95% was achieved under all the examined conditions, confirming the effectiveness of the process. The proposed electrochemical treatment was comparable with other AOPs in terms of energy consumption, and it can be considered as an alternative to other processes for ground water treatment. (C) 2010 Society of Chemical Industry
Electrochemical treatment of simulated ground water containing MTBE and BTEX with BDD anodes
MASCIA, MICHELE;VACCA, ANNALISA;PALMAS, SIMONETTA;DA POZZO, ANNA
2011-01-01
Abstract
BACKGROUND: Benzene, toluene, ethylbenzene, xylene (BTEX) and oxy-fuels such as methyl tert-butyl ether (MTBE) are typical contaminants of ground waters. Biological and physical techniques are often ineffective in removing these compounds, while promising results were obtained with advanced oxidation processes (AOPs), which are based on oxidation by hydroxyl radicals. Electrochemical oxidation with boron doped diamond (BDD) anodes occurs by OH radicals generated from water oxidation, so that it may be considered as an alternative to other AOPs. RESULTS: An experimental study on the electrochemical removal of MTBE and BTEX with BDD anodes from water with low organic concentrations and low conductivity is presented. The kinetics of the process was investigated by batch electrolyses: the removal of MTBE and benzene was controlled by the mass transfer towards the anode, while a further reaction bulk contribution was found for alkylbenzenes. The process was tested in continuous mode and the energy consumption was evaluated and compared with other AOPs. CONCLUSIONS: Removal of the pollutants higher than 95% was achieved under all the examined conditions, confirming the effectiveness of the process. The proposed electrochemical treatment was comparable with other AOPs in terms of energy consumption, and it can be considered as an alternative to other processes for ground water treatment. (C) 2010 Society of Chemical IndustryI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.