Kinetic behavior of anti-inflammatory drug ibuprofen in aqueous medium during its degradation by electrochemical advanced oxidation.
The electrochemical abatement of the drug ibuprofen (2-(4-isobutylphenyl)propionic acid) from aqueous solution has been carried out by anodic oxidation. The electrolyses have been performed at constant current using a small, undivided cell equipped with a Pt or thin-film boron-doped diamond (BDD) anode and a carbon-felt cathode. The results have shown that ibuprofen has been destroyed under all the conditions tested, following pseudo-first-order kinetics; however, BDD enables higher removal rates than Pt, because the former produces greater quantity of (•)OH. Using BDD anode, the pseudo-first-order rate constant increased with applied current and when NaCl replaced Na2SO4 as supporting electrolyte, while it is almost unaffected by ibuprofen concentration. Mineralization of ibuprofen aqueous solutions was followed by total organic carbon (TOC) measurements. After 8 h of electrolysis, TOC removal varied from 91% to 96% applying a current in the range of 50-500 mA. The reaction by-products were quantified by chromatographic techniques, and in particular, aliphatic acids (oxalic, glyoxylic, formic, acetic, and pyruvic) have been the main intermediates formed during the electrolyses. The absolute rate constant for the oxidative degradation of ibuprofen have also been determined, by competition kinetic method, as 6.41 × 10(9) M(-1) s(-1).
Laboratoire Géomatériaux et Environnement, Université Paris-Est Marne-la-Vallée, 5 boulevard Descartes, Champs-sur-Marne, 77454 Marne-la-Vallée, Cedex 02, France.
Silvia Loaiza
SL
Ambuludi
Marco
M
Panizza
Nihal
N
Oturan
Ali
A
Özcan
Mehmet A
MA
Oturan
D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000737:chemistry*; D001895:Boron; D002851:Chromatography, High Pressure Liquid; D002852:Chromatography, Ion Exchange; D018130:Diamond; D004566:Electrodes; D004572:Electrolysis / Q000379:methods*; D007052:Ibuprofen / Q000737:chemistry*; D007700:Kinetics; D010084:Oxidation-Reduction; D010984:Platinum; D014874:Water Pollutants, Chemical / Q000737:chemistry*; D018508:Water Purification / Q000379:methods*
D000894:Anti-Inflammatory Agents, Non-Steroidal; D014874:Water Pollutants, Chemical; D010984:Platinum; D018130:Diamond; D001895:Boron; D007052:Ibuprofen