title: Removal of Mefenamic acid from aqueous solutions by oxidative process: Optimization through experimental design and HPLC/UV analysis.
abstract: Mefenamic acid (MEF) is a non-steroidal anti-inflammatory drug indicated for relief of mild to moderate pain, and for the treatment of primary dysmenorrhea. The presence of MEF in raw and sewage waters has been detected worldwide at concentrations exceeding the predicted no-effect concentration. In this study, using experimental designs, different oxidative processes (H2O2, H2O2/UV, fenton and Photo-fenton) were simultaneously evaluated for MEF degradation efficiency. The influence and interaction effects of the most important variables in the oxidative process (concentration and addition mode of hydrogen peroxide, concentration and type of catalyst, pH, reaction period and presence/absence of light) were investigated. The parameters were determined based on the maximum efficiency to save time and minimize the consumption of reagents. According to the results, the photo-Fenton process is the best procedure to remove the drug from water. A reaction mixture containing 1.005 mmol L(-1) of ferrioxalate and 17.5 mmol L(-1) of hydrogen peroxide, added at the initial reaction period, pH of 6.1 and 60 min of degradation indicated the most efficient degradation, promoting 95% of MEF removal. The development and validation of a rapid and efficient qualitative and quantitative HPLC/UV methodology for detecting this pollutant in aqueous solution is also reported. The method can be applied in water quality control that is generated and/or treated in municipal or industrial wastewater treatment plants.
authors.affiliation: Escola de Artes, Ciências e Humanidades, Universidade de São Paulo, 03828-000, São Paulo, SP, Brazil; Instituto de Química de São Carlos, Universidade de São Paulo, Caixa Postal 780, 13560-970, São Carlos, SP, Brazil. Electronic address: renatacolomb@gmail.com.
authors.forename: Renata
authors.initials: R
authors.lastname: Colombo
authors.affiliation: Instituto de Química de São Carlos, Universidade de São Paulo, Caixa Postal 780, 13560-970, São Carlos, SP, Brazil.
authors.forename: Tanare C R
authors.initials: TC
authors.lastname: Ferreira
authors.affiliation: Instituto de Química de São Carlos, Universidade de São Paulo, Caixa Postal 780, 13560-970, São Carlos, SP, Brazil.
authors.forename: Renato A
authors.initials: RA
authors.lastname: Ferreira
authors.affiliation: Instituto de Química de São Carlos, Universidade de São Paulo, Caixa Postal 780, 13560-970, São Carlos, SP, Brazil.
authors.forename: Marcos R V
authors.initials: MR
authors.lastname: Lanza
mesh_terms: D002384:Catalysis; D002851:Chromatography, High Pressure Liquid; D006861:Hydrogen Peroxide / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D008528:Mefenamic Acid / Q000737:chemistry / Q000302:isolation & purification*; D010070:Oxalates / Q000737:chemistry; D010084:Oxidation-Reduction; D012722:Sewage; D014466:Ultraviolet Rays; D014865:Waste Disposal, Fluid / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000302:isolation & purification*
chemical_list: D010070:Oxalates; D012722:Sewage; D014874:Water Pollutants, Chemical; C034942:ferrioxalate; D008528:Mefenamic Acid; D006861:Hydrogen Peroxide
keywords: Advanced oxidative processes; Anti-inflammatory; Experimental designs; Mefenamic acid; Photo-fenton reaction