Photocatalytic degradation of Perchloroethylene by a lab-scale continuous-flow annular photoreactor packed with glass beads carbon-doped TiO2 nanoparticles

In this study, the amount of photocatalytic degradation of perchloroethylene in the gas phase was investigated by a fixed bed continuous-flow tubular photoreactor. The photoreactor consists of a cylindrical glass tube, was filled with glass beads coated with nanoparticles of TiO2, TiO2 doped carbon (TiO2-C). These nanoparticles were synthesized by the sol-gel method and deposited on glass beads using the sol-gel dip technique. X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transforms infrared spectroscopy (FT-IR), and diffuse reflectance spectroscopy (DRS) were used for the characterization of synthesized materials. The effect of different parameters such as relative humidity, residence time, PCE concentration on the photocatalytic degradation process was investigated by ultraviolet irradiation to achieve the highest possible degradation efficiency. The PCE degradation and byproduct species were monitored and identified with a gas chromatography-mass spectrometer device (GC-MS). Under the optimum experimental conditions, the photocatalytic activities of TiO2, TiO2-C were investigated and compared together. The results showed that photocatalytic activity of TiO2 for degradation of PCE was extremely increased when doped with carbon. For TiO2-C catalyst, under UV irradiation (3000 ppm initial PCE concentration, 30% humidity and 1 min residence time) approximately 96% of the initial PCE was degraded.