title: Advanced oxidation processes for treatment of effluents from a detergent industry.
abstract: Ozonation, catalytic ozonation, Fenton's and heterogeneous Fenton-like processes were investigated as possible pretreatments of a low biodegradable and highly toxic wastewater produced by a detergent industry. The presence of a Mn-Ce-O catalyst in ozonation enhances the biodegradability and improves the degradation at low pH values. However, a high content of carbonyl compounds adsorbed on the recovered solid indicates some limitations for real-scale application. A commercial Fe2O3-MnOx catalyst shows higher activity as well as higher stability concerning carbon adsorption, but the leaching of metals is larger than for Mn-Ce-O. Regarding the heterogeneous Fenton-like route with an Fe-Ce-O catalyst, even though a high activity and stability are attained, the intermediates are less biodegradable than the original compounds, indicating that the resulting effluent cannot be conducted to an activated sludge post-treatment. The highest enhancement of effluent biodegradability is obtained with the classic homogeneous Fenton's process, with the BOD5/COD ratio increasing from 0.32 to 0.80. This process was scaled up and the treated effluent is now safely directed to a municipal wastewater treatment plant.
authors: Centro de Investigação em Engenharia dos Processos Químicos e Produtos da Floresta, GERSE, Group on Environmental, Reaction and Separation Engineering, Department of Chemical Engineering, Faculty of Sciences and Technology, University of Coimbra, Pólo II-Rua Silvio Lima, 3030-790 Coimbra, Portugal.
authors: Rui C
authors: RC
authors: Martins
authors: Adrián M T
authors: AM
authors: Silva
authors: Sérgio
authors: S
authors: Castro-Silva
authors: Paulo
authors: P
authors: Garção-Nunes
authors: Rosa M
authors: RM
authors: Quinta-Ferreira
mesh_terms: D001420:Bacteria, Aerobic / Q000378:metabolism*; D003902:Detergents / Q000737:chemistry* / Q000378:metabolism*; D006861:Hydrogen Peroxide / Q000737:chemistry; D007220:Industrial Waste / Q000517:prevention & control; D007501:Iron / Q000737:chemistry; D010100:Oxygen / Q000378:metabolism*; D014874:Water Pollutants, Chemical / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism*; D018508:Water Purification / Q000379:methods*
chemical_list: D003902:Detergents; C045076:Fenton's reagent; D007220:Industrial Waste; D014874:Water Pollutants, Chemical; D006861:Hydrogen Peroxide; D007501:Iron; D010100:Oxygen