Heterogeneous photocatalytic systems: Influence of some operational variables on actual photons absorbed by aqueous dispersions of TiO2

The photooxidation of phenol in aqueous solution in the presence of polycrystalline TiO₂ powder was used as "test" reaction in order to investigate the influence of incident light intensity and of some physical and chemical parameters on the actual absorbed photon flows and on the reactivity. The physical parameters investigated were the surface area and the size of particles while the chemical parameters investigated were the initial pH of the dispersion and the presence in the reacting medium of additives affecting the photoreactivity such as Cl⁻ and H₂O₂.