The individual and simultaneous photocatalytic reduction of poisonous Ni(II) ion, coupled with photooxidation of the pollutant naphthalene (NA), were examined with trace amounts of commercial titania nanoparticles. A direct imposed irradiation photo-reactor was employed. The effect of major operational parameters, solution pH and temperature was investigated. The co-presence of naphthalene and Ni(II) ion gives a better separation of charge carriers, resulting enhancement in the both naphthalene oxidation and nickel ion reduction. Pseudo first order reactions are proceeding. As a relevant criterion, the electrical energy consumption and other criteria were evaluated and were compared with other previously reported processes.