Kinetics of Ibuprofen Degradation in Aqueous Solution by the Action of Dielectric-Barrier Discharge in Oxygen

The kinetic features of the degradation of ibuprofen (IBU) in its aqueous solution by the action of atmospheric-pressure dielectric-barrier discharge in an oxygen stream have been studied. The range of concentrations was (8.6–42.8) mg/L, and the range of power input to the discharge was (7–57) W. It has been found that the degradation process is formally described by the first-order rate equation in ibuprofen concentration. Degradation rates, effective degradation rate constants, and degrees of destruction have been determined. At a fixed discharge power, the constants do not depend on the initial concentration of the solution. Typical values of the rate constants are ~(0.2–0.7) s⁻¹. Based on these data, energy yields and degrees of degradation at various discharge powers (discharge currents) have been calculated. The energy yields of degradation are in the range of (4–9) × 10⁻³ molecule per 100 eV of input energy, with the degree of degradation reaching 100%. It has been found that carboxylic acids and aldehydes are formed as a result of IBU degradation.