Using physical–chemical properties of reactants to estimate the performance of photocatalytic oxidation air cleaners

• Perform detailed review of the photocatalytic reaction mechanisms with TiO2 catalysts.
• Develop a correlation based on physical–chemical properties and reaction rate of organic compounds.
• Compare the performance of three catalysts and study the humidity effect on removal efficiency of system.

Various ultraviolet photocatalytic oxidation (UV–PCO) technologies are being used to eliminate or minimize different types of indoor air pollution, namely volatile organic compounds (VOCs). However, the removal efficiency of such air cleaning systems for different kind of VOCs could be challenging or completely unpredictable at different indoor environment conditions. This study presents a new systematic experimental method for measuring the performance of UV–PCO systems for different operational test conditions. The experiments were carried out using a continuous single pass system setup with three different types of TiO2 catalysts at high airflow rate and ambient indoor air temperature and humidity levels. The adsorption isotherm for each catalyst was determined individually to find a correlation for each test compounds. The relationship between the PCO rate constant and ionization potential (IP), as a physical and chemical property of selected alcohols compounds was investigated at the steady-state condition. The developed reaction rate correlations can be used as a design parameter to quantify the removal efficiency of other VOCs with the tested experimental system setup.