Study On Preparation Of Suppored TiO₂ Purifying Material And Degradation Of Formaldehyde

Formaldehyde is dangerous substance with high toxicity which can induce cancer and abnormality. People have paid more and more attention to superscale of formaldehyde indoors. The study is mainly based on TiO2 application in gas phase photocatalysis, aiming at indoor formaldehyde, a series of correlative experiments were carried on, including preparation of TiO2 photocatalyst, loading and photocatalytic degradation of formaldehyde. The results have proved reference value to photocatalysis technology in purifying air.Titanium dioxide films were prepared on glass substrates by sol-gel method and the best preparation conditions was developed. Designed and made a coating device for prepared TiO2 thin film. The TiO2 thin film purification ability was examined through the degeneration certain density methyl orange experiment. The influences of calcining temperature, coating layer, the speed of rising temperature, the UV illumination on the photocatalytic activities of the TiO2 thin films were also investigated. The experimental results showed that the TiO2 thin films had the higher photocatalytic activity when glass was calcinated at 500℃, with 5℃/min rising temperature speed and was coated three layers.A reaction device was designed for formaldehyde photocatalytic degradation. The photocatalytic degradation behavior of gaseous formaldehyde was studied and the influence factors of formaldehyde photocatalytic degradation, such as initial concentration of gaseous formaldehyde, titanium dioxide quantity, UV illumination were also studied. The experimental results showed that the percentage of degrading gaseous formaldehyde was the highest when the concentration of gaseous formaldehyde was 95.18μg/L, the percentage of degrading gaseous formaldehyde increased with the increasing of quality of TiO2, the percentage of degrading gaseous formaldehyde with UV illumination is better than sunlight.