Solar photocatalytic degradation of o-phenylenediamine by heterogeneous CuO/X zeolite catalyst

The present study involves the photocatalytic degradation of o-phenylenediamine (OPD) employing heterogeneous photocatalytic process. The CuO/X zeolite catalyst was prepared by supporting CuO on the zeolite X matrix and photocatalytic activity of the catalyst under solar irradiation was investigated. The parent zeolite, ion exchanged media and photocatalyst were characterized by atomic absorption spectroscopy, X-ray diffraction, infrared spectroscopy, BET and thermal analysis methods. The degradation process was monitored during the experimental runs through UV/Vis absorption as well as COD and TOC concentration determination and HPLC methods. Effect of key operating factors affecting photocatalytic degradation efficiency of OPD was investigated and the optimum values were obtained as: 0.3 g L−1 of photocatalyst, 25 ppm for o-phenylenediamine, pH of 7.1, 20 mM of H2O2 and 10 mM of KBrO3. The obtained results showed that photocatalysis under sunlight is effective process for the degradation of OPD and the degradation kinetic of OPD obeys Langmuir–Hinshelwood equation.

► Aqueous solution of o-phenylenediamine was degraded by zeolite X incorporated CuO under sunlight irradiation.
► CuO inside the zeolite is active center for degradation.
► The results of TOC and COD and UV–vis and formation of NO3−, NO2− and NH4+ indicate complete degradation of pollutant.