Mechanism pathway and kinetics of p-cresol photocatalytic degradation over titania nanorods under UV–visible irradiation

Abstract Titania nanorods (TNRs) in pure anatase phase were synthesized by a hydrothermal technique and calcined at 450 °C. The material was characterized by X-ray diffraction (XRD), N 2 adsorption, transmission electron microscopy (TEM), UV-DR spectroscopy, and X-ray photoelectron spectroscopy (XPS). The photocatalytic degradation of p -cresol was carried out under UV–vis irradiation. The photodecomposition of p -cresol could be expressed by pseudo-first order in Langmuir–Hinshelwood kinetic model. The rate constant obtained of the TNRs catalyst was higher than that over P25 catalyst. Intermediates produced during the reaction were 4-methylcatechol, 4-hydroxybenzoic acid, 4-hydroxybenzyl alcohol and 4-hydroxybenzaldehyde. All intermediates are indicated to be less hazardous compared to p -cresol. More than 96% TOC mineralization was achieved during the degradation time. In addition, the reaction mechanism and pathway has been proposed and the rate constants for each elementary reaction were evaluated.