Naphthalene removal from wastewater sources was investigated in a batch slurry system using photocatalytic process as a subset of advanced oxidation processes. At low concentrations of naphthalene, the pseudo first order rate equation on the base of Langmuir–Hinshelwood model described the degradation kinetics very well. Also, the photocatalytic process was employed to evaluate the effect of various operational parameters such as agitation speed (0–200 rpm), injected air flow (0–6 L/h), TiO2 concentration (0–3 g/L) and UV power intensity (0–24 W). Experimental results demonstrated that by increment in the mass transfer coefficient, the agitation speed positively affected naphthalene degradation. Due to the “screening effect”, concentration of TiO2 showed an optimum amount equal to 2 g/L. Aeration to the solution affected the amount of oxygen as an electron scavenger and so enhanced naphthalene degradation rate. Meanwhile in the absence of UV radiation to the solution, the rate of naphthalene removal decreased significantly. In other hand, augmentation in UV radiation more than 8 W had a low influence on the amount of removed naphthalene and reaction rate.

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