OH-initiated AOPs degradation mechanism of ibuprofen in aqueous environments

Abstract

As a common pharmaceutical and personal care product, ibuprofen (IBP) is regarded as an important pollutant in aqueous environments. In this paper, the OH-initiated advanced oxidation processes (AOPs) degradation mechanism and its subsequent reaction mechanism with IBP were studied at the M06-2x/6-311++G(2d, p)//M06-2x/6-31+G(d,p) level. The frontier electron density and bond dissociation energy were analyzed. In addition, profiles of the potential energy surface were constructed, and all the possible pathways were discussed. H-atom abstraction is the most important mechanism. The dominant products were IBAP, 2-[4-(1-hydroxyisobutyl)phenyl]propionic acid, and 1-(4-isobutylphenyl)-1-ethanol, which is in good agreement with the experimental results.