title: Coupling coagulation, flocculation and decantation with photo-Fenton process for treatment of industrial wastewater containing fipronil: Biodegradability and toxicity assessment.
abstract: This work reports the treatment of wastewater containing the insecticide fipronil, integrating coagulation, flocculation and decantation in the photo-Fenton process. Under the best concentration of the coagulant - Fe(3+) (56 mg L(-1)), the suspended solids and total fipronil concentrations decreased respectively from 7000 and 20.9 mg L(-1) to 590 and 2.2 mg L(-1), but without reduction in dissolved organic carbon - DOC (1760 mg C L(-1)) and acute toxicity to Artemia salina (100%). Subsequently, the photo-Fenton process was applied as alternative of pre- or complete treatment, taking into account toxicity and biodegradability (given by biochemical oxygen demand after five days - BOD5/chemical oxygen demand - COD ratio) assessment. The best DOC and COD removal were reached with 60 and 6723 mg L(-1) of Fe(2+) and H2O2, respectively. Under these conditions, after 60 min of irradiation, 57% of DOC and 74% of COD were removed, with a decrease in acute toxicity to A. salina from 100% to 13% and an increase in the BOD5/COD ratio from 0.052 to 1.0. With these parameters, the integration of coagulation/flocculation/decantation and photo-Fenton processes may be an alternative to the pre- or complete treatment of wastewater containing fipronil.
authors.affiliation: Universidade Federal de Uberlândia, Instituto de Química, 38400-902 Uberlândia, MG, Brazil. Electronic address: batuirafilho@yahoo.com.br.
authors.forename: Batuira Martins
authors.initials: BM
authors.lastname: da Costa Filho
authors.affiliation: Universidade Federal de Uberlândia, Instituto de Química, 38400-902 Uberlândia, MG, Brazil. Electronic address: v-aldis@hotmail.com.
authors.forename: Valdislaine Maria
authors.initials: VM
authors.lastname: da Silva
authors.affiliation: Universidade Federal de Uberlândia, Instituto de Química, 38400-902 Uberlândia, MG, Brazil. Electronic address: josquim01@yahoo.com.br.
authors.forename: Jader de Oliveira
authors.initials: Jde O
authors.lastname: Silva
authors.affiliation: Universidade Federal de Uberlândia, Instituto de Química, 38400-902 Uberlândia, MG, Brazil. Electronic address: aehmachado@gmail.com.
authors.forename: Antonio Eduardo
authors.initials: AE
authors.lastname: da Hora Machado
authors.affiliation: Universidade Federal de Uberlândia, Instituto de Química, 38400-902 Uberlândia, MG, Brazil. Electronic address: alamtrovo@ufu.br.
authors.forename: Alam Gustavo
authors.initials: AG
authors.lastname: Trovó
mesh_terms: D000818:Animals; D001156:Artemia / Q000187:drug effects; D001673:Biodegradation, Environmental; D057919:Biological Oxygen Demand Analysis; D005427:Flocculation; D006861:Hydrogen Peroxide / Q000737:chemistry*; D007501:Iron / Q000737:chemistry*; D010084:Oxidation-Reduction; D011720:Pyrazoles / Q000032:analysis / Q000633:toxicity; D023382:Toxicity Tests, Acute; D014865:Waste Disposal, Fluid / Q000379:methods*; D062065:Wastewater / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000633:toxicity; D018508:Water Purification / Q000379:methods*
chemical_list: D006861:Hydrogen Peroxide; D007501:Iron; D011720:Pyrazoles; D062065:Wastewater; D014874:Water Pollutants, Chemical; C045076:Fenton's reagent; C082360:fipronil
keywords: Advanced oxidation process; Degradation; Effluent; Environmental impact; Insecticide; Wastewater treatment