Dynamic behavior of hydroxyl radical in sono-photo-Fenton mineralization of synthetic municipal wastewater effluent containing antipyrine.
The aim of this study was to examine the kinetics of the different mechanisms (radical pathway, photolysis, molecular reaction with H2O2and reaction with ultrasonically generated oxidative species) involved in the homogeneous sono-photoFenton (US/UV/H2O2/Fe) mineralization of antipyrine present in a synthetic municipal wastewater effluent (ASMWE). The dynamic behavior of hydroxyl (HO) radical generation and consumption in mineralization reaction under different systems was investigated by measuring hydroxyl radical concentration during the reaction. The overall mineralization process was optimized using a Central-Composite Experimental Design (CCED) with four variables (initial concentrations of H2O2and Fe(II), amplitude and pulse length). The response functions (pseudo-first order mineralization kinetic rate constants) were fitted using neural networks (NNs). Under the optimal conditions ([H2O2]o=500mgL-1, [Fe(II)]o=27mgL-1, Amplitude (%)=20andPulse length=1), the TOC removal was 79% in 50min. The radical reaction in the bulk solution was found be the primary mineralization pathway (94.8%), followed by photolysis (3.65%), direct reaction with H2O2(0.86%), and reaction by ultrasonically generated oxidative species (0.64%). The role of the Fe catalyst on the radical reaction and the presence of refractory intermediates towards hydroxyl radical were also studied.
Department of Chemical Engineering, Grupo IMAES, Escuela Técnica Superior de Ingenieros Industriales, Instituto de Investigaciones Energéticas y Aplicaciones Industriales (INEI), University of Castilla-La Mancha, Avda. Camilo José Cela 3, 13071 Ciudad Real, Spain.
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Expósito
Department of Chemical Engineering, Grupo IMAES, Escuela Técnica Superior de Ingenieros Industriales, Instituto de Investigaciones Energéticas y Aplicaciones Industriales (INEI), University of Castilla-La Mancha, Avda. Camilo José Cela 3, 13071 Ciudad Real, Spain. Electronic address: josemaria.monteagudo@uclm.es.
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Monteagudo
Department of Chemical Engineering, Grupo IMAES, Escuela Técnica Superior de Ingenieros Industriales, Instituto de Investigaciones Energéticas y Aplicaciones Industriales (INEI), University of Castilla-La Mancha, Avda. Camilo José Cela 3, 13071 Ciudad Real, Spain.
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Department of Chemical Engineering, Grupo IMAES, Escuela Técnica Superior de Ingenieros Industriales, Instituto de Investigaciones Energéticas y Aplicaciones Industriales (INEI), University of Castilla-La Mancha, Avda. Camilo José Cela 3, 13071 Ciudad Real, Spain.
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Fernández
D000983:Antipyrine / Q000737:chemistry*; D002384:Catalysis; D002947:Cities; D006861:Hydrogen Peroxide / Q000737:chemistry*; D017665:Hydroxyl Radical / Q000737:chemistry*; D007501:Iron / Q000737:chemistry*; D008903:Minerals / Q000737:chemistry*; D055668:Photochemical Processes; D013010:Sonication; D062065:Wastewater / Q000737:chemistry*
D000983:Antipyrine; D006861:Hydrogen Peroxide; D017665:Hydroxyl Radical; D007501:Iron; D008903:Minerals; D062065:Wastewater; C045076:Fenton's reagent
Hydroxyl radical concentration; Kinetics; Pharmaceuticals; Sono-photo-Fenton