Research on Decomposition of Formaldehyde by E.P.D. Method Preparing TiO2 Photocatalyst

• Main Authors: Hung-Wei Cheng, 鄭弘偉
• Other Authors: 卓清松
• Format: Others
• Language: zh-TW
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/35zdem

碩士 === 國立臺北科技大學 === 能源與冷凍空調工程系碩士班 === 96 === Regarding the principle of electrophoretic deposition, under an added voltage, the charged particles in the suspension fluid are driven to move towards the electrode being opposite to its electric charge, and further deposited on the base plate. This study employed electrophoretic deposition to let titanium oxide (TiO2) clad on the stainless steel filter, and then observed and compared the difference appeared on the surface of TiO2 thin films prepared by the suspension fluids of different cconcentrations, pH values, voltages and sintering temperatures. Formaldehyde is one of the commonest air pollutants indoors. The study installed in a set of enclosed air-conditioning chamber with adjustable temperature and humidity with a photocatalytic fiber prepared under the best electrophoretic condition, intending to reduce the concentration of the organic gas of formaldehyde to achieve the function of air purification. Under the conditions that the air-conditioning chamber was preset at an indoor temperature of 21℃ in winter and 26℃ in summer, a humidity of 50%RH, and a circulated wind speed of 0.7m/s, and when the number of TiO2 filters and the ultraviolet illumination were taken as the operation parameters, the study investigated the influence on the photocatalytic decomposition of the pollutant of formaldehyde in the air-conditioning system. The research results show that the higher the temperature, the better the photocatalytic efficiency. As the ultraviolet illumination is greater, the photocatalytic efficiency is better. As the number of photocatalytic filters increases, the contact area between pollutant and photocatalytic surface is enlarged. Therefore, the photocatalytic efficiency becomes better. In the experiment, the greatest efficiency of background natural absorption reaches 13.21% at 21℃, and 15.93% at 26℃. However, the UV photolytic efficiency is comparatively not so obvious, being 3.57% at 21℃, and 4.48% at 26℃. The greatest photocatalytic efficiency can reach 25.59% at 21℃, and 36.39% at 26℃. The overall removal efficiency of formaldehyde can reach 51.15% at 21℃, and 55.06% at 26℃. Using the photocatalytic filters made by electrophoretic preparation by this graduate institute, the organic gas of formaldehyde can be effectively reduced, achieving the effect of clean indoor air and improving the health of human body.