Theoretical Investigation on Nano TiO₂ Photocatalytic Oxidation of VOCs

Controlling mechanisms for photocatalytic degradation of volatile organic compounds by nano TiO₂ catalyst are found to be mass transfer, diffusion, adsorption and photochemistry. A mathematical model for the degradation process is developed by incorporating these mechanisms in a plane plate air purification physical model. Finite difference method is employed to solve the governing equation and boundary conditions. The computation results are validated using the data from experiments. The model is then used to investigate the effects of some key factors on the degradation of formaldehyde including UV light intensity, UV light attenuation coefficient, adsorption, catalyst thickness, and flow rate.