Study on Effects of Nano-photocatalysis and Non-thermal Plasma on the Removal of Indoor HCHO

摘要

Photocatalysis is an emerging and promising technology for indoor air purification. This photocatalytic oxidation (PCO) method is effective in the case of a higher pollutant concentration, but its wide application in indoor air purification is limited due to the low level of indoor air contaminants. In order to improve the removal of pollutants in indoor air, we have evaluated the photocatalytic performance over the nanosized TiO_2 particles immobilized on the surface of an activated carbon (AC) filter for the removal of formaldehyde (HCHO). However the pollutant removal capacity is low at the low level of indoor HCHO over the TiO_2/AC film because the predominant influence of residence time during this reaction. In order to improve the photocatalytic removal amount of formaldehyde (HCHO) in indoor air, we studied the combining effect of photocatalysis technology with a non-thermal plasma (NTP) technology on the removal of in door HCHO. Two different plasma electrode configurations, that is wire-to-plate and needle-to-plate electrode configuration, were built and the removal of HCHO was studied by experiment. The experimental results showed that the wire-to-plate electrode configuration is more effective for the HCHO removal than the needle-to-plate electrode configurations. The experimental results using wire-to-plate electrode configuration showed that the removal of HCHO can be enhanced and the removal amount of indoor HCHO can be improved by the combination of PCO and NTP and the combination of PCO and NTP showed the synergetic effect for the indoor HCHO removal. So the combination of PCO and NTP might be a good route for the practical application of photocatalytic technology in indoor air purification.