(24e) Photocatalytic Oxidation Systems for Indoor Air Cleaning Applications

The use of photocatalytic oxidation (PCO) is a promising component of an effective indoor air cleaning system. Numerous PCO studies have focused on the evaluation and improvement of the system for a typical indoor environment. Development of energy-efficient photocatalysts is one of the vital aspects that can facilitate the commercialization of PCO air cleaning devices. One of the recent advances on photocatalyst development is the synthesis of 2% C- and V-doped TiO₂. The catalyst contains some carbon and 2% vanadium. Experimental studies on a laboratory scale have confirmed the catalyst's comparable activity both under visible light and dark conditions. This prominent characteristic of the catalyst combined with the potential utilization of the visible light spectrum from fluorescent lamps and solar radiation make the catalyst an attractive element of energy-efficient PCO air cleaning systems. This study is one of the first attempts to investigate the potential application in a typical indoor air environment of the two promising PCO design options that incorporates the C and V co-doped TiO₂. Mathematical modeling and simulation techniques were utilized to assess the use of packed bed and thin film systems in the photocatalytic oxidation of VOCs that are commonly found in offices, residential buildings, and other facilities. Using various operating conditions, the pressure drop through the packed bed and the influence of mass transfer limitations on the removal rate of the contaminants indoors for the two systems were investigated.

Keywords: air cleaning, energy-efficient, indoor air, mass transfer, mathematical model, packed bed, photocatalytic oxidation, simulation, thin films, visible light, VOCs