Study of formaldehyde photocatalytic degradation using nano TiO2

In this study, formaldehyde, one of the major volatile organic compounds, is degraded using nano TiO2 photocatalysis for improving indoor air quality. Polytetrafluoroethylene filter, a low cost and commonly used material in industry, is successfully employed as the substrate for nano TiO2 photocatalyst coating at room temperature. A specific experimental set-up that is similar to actual air purification system is developed for the testing. The effects on formaldehyde photocatalytic degradation rate of some key factors are investigated. These factors include initial concentration, stream flow rate, reaction temperature, light source intensity, and relative humidity. Within the experimental ranges, the degradation rate increases with the enhancement of initial concentration and light intensity. The stream flow rate and reaction temperature have dual effects on the degradation rate. The degradation rate is relatively high under low relative humidity.