The photocatalytic degradation of phenol and other phenolic compounds can follow different pathways depending on the reaction conditions. It is found that the photocatalytic oxidation of phenol is faster in acidic pHs with an optimum pH value of 3.2. On the basis of experimental data, it is concluded that the photocatalytic oxidation of phenol, ortho-dihydroxybenzene (o-DHB), para-dihydroxybenzene (p-DHB), and 1,4-benzoquinone (1,4-BQ) can all be described with a series-parallel reaction scheme. The present- study reports a detailed reaction network incorporating possible reaction steps based on data obtained for the oxidation of phenol and its three aromatic intermediates. Four carboxylic acids (fumaric acid, maleic acid, oxalic acid, and formic acid) are detected as intermediates in the photocatalytic oxidation of phenol, o-DHB, p-DHB, and 1,4-BQ,.suggesting that, in the oxidation of any phenolic compounds, these acids are part of the oxidation breakdown of more complex molecules. Additionally, two kinetic models are proposed with different degrees of complexity. A first model (KM#1) contains enhancements to that proposed by Salaices et al. (Chem. Eng. Sci. 2004, 59, 3) and helps predict the formation and disappearance of aromatic compounds only. In a second kinetic model (KM#2), a lumped acid concentration and CO2 formation are incorporated to account for the formation and disappearance of carboxylic acids as well as for the overall rate of mineralization. Both models provide a very good fit of the experimental data and work for a wide range of phenol concentrations (20-50 ppm C in phenol). Parameters estimates with statistical indicators for both models are also reported in this study.