Design of UV-C LED Photocatalytic Reactor for Degradation of Volatile Organic Compounds
Ultraviolet light-emitting diodes are slowly replacing the applications of conventional UV lamps due to smaller foot-prints, non-toxic operation, and design flexibility of LEDs . Mercury-vapor UV lamp is a common source for high-energy ultraviolet photons (UV-C) in many applications. Photocatalytic degradation of VOC is one of the applications, where the conventional UV lamps are installed for the degradation of indoor pollutants. Typically, photocatalytic reactors are hollow-cylindrical tubes with the UV lamp placed at the center axis to fully illuminate the photocatalyst coated on the inner sidewall of the reactor . Unlike UV lamps, it is not straightforward to use the UV-C LEDs to design a photocatalytic reactor for the VOC degradation, because UV-C LEDs are usually pointsource with the limited light emission angle . Therefore, the emission angle of the UV-C LED is a key factor affecting the illumination of the photocatalyst in a LED-based cylindrical photocatalytic reactor.