Background and purpose: Aniline is widely used as raw material in many chemical industries. The aim of this study was to survey the photocatalytic degradation of aniline using magnesium oxide nanoparticles from aqueous solutions.

Materials and methods: An experimental study was carried out in a 2 L volume batch reactor. Various parameters such as pH (3-11), dose of nanoparticles (0.1-1), contact time (15-120 min), initial aniline concentration (5-250 mg/L) and irradiation source power (8, 15 and 30 W) were investigated. The concentration of residual aniline was measured by UV spectrophotometer at λ_max of 198 nm.

Results: The results showed that photocatalytic process of nMgO+UV could effectively remove aniline from effluent. The optimal solution pH and dose of nanoparticles for 8 W, 15 W and 30 W UVA lamp were 7.0 and 0.6 g/L, 7 and 0.4 g/L, and 7 and 0.4 g/L, respectively. In 30 min optimum contact time the photocatalytic degradation efficiency decreased when the concentration of aniline was increased. In optimum conditions (5 mg/L of aniline and 30 min reaction time) the aniline removal efficiency was 90.63 % and COD removal was 87.02%.

Conclusion: The photocatalytic process of nMgO+UV can be used as a suitable technique for aniline removal from aqueous solutions.