| Photocatalytic degradation of ethylbenzene was studied in glass reactors coated with TiO2 on their inner surfaces. The percent conversion of the ethylbenzene was dependent on inlet concentration, humidity, oxygen concentration, temperature, thickness of TiO2 catalyst, retention time, and size of the reactor diameter, and all of these factors were investigated. The air stream with ethylbenzene was conducted through the coated glass reactor in which a 4-watt UV light bulb was inserted at the center. Destruction levels higher than 90% were achieved when the appropriate conditions were set. Oxygen and humidity play an important role in ethylbenzene photocatalytic oxidation. The reaction rate for ethylbenzene conversion was suppressed when the operating temperature or the inlet concentration increased. No by-product was detected by GC/MS during the photoreaction of 5 ppm ethylbenzene inlet concentration. Homogeneous photolysis was observed only at a high reactant inlet concentration (>50 ppm).; The ethylbenzene reaction constant and the adsorption equilibrium constant of the small glass reactors can be evaluated by the equation Langmuir-Hinshelwood and Beer-Lambert's law. The overall reaction rates of large glass reactors are predominantly controlled by the mass transfer diffusion. |
