The Application Research On Nanometer Composite Material In Decomposing Indoor Low Concentration VOCs

As the development of our society and improvement of living standard, Indoor Air Quality is paid more and more attention by general public. For the popularity of indoor decoration, the application of HVAC facilities and the using of daily chemical product these years, indoor air is greatly polluted by Volatile Organic Compounds, which have features of low concentration, various kinds, great hazard and long-lasting. However, in our country, the main measure for dealing that is to use absorption, which has a great deal of inconveniences. Recently, photocatalytic nanometer titanium dioxide is frequently used for VOCs cleaning, but there are still many problems in the low efficiency of nanometer titanium dioxide photocatalysis.This paper first deals with the relevant theory of absorption. We adopt Polanyi potential theory to build module of low concentration VOCs absorption. Meanwhile, we use Dubinin-Radushkevich equation describes its mathematical and physical features and use micropore volume V₀ and standard feature absorption coefficient k_s to describe the most important two key factors. Secondly, it refers to the mechanism of nanometer titanium dioxide photocatalysis and its visible light transformation method.Thirdly, we combine visible light nanometer TiO₂ with absorbent together for degradation of low concentration VOCs, in that can use its mutual reinforcement effect for improvement of performance, and we split absorption and photocatalysis apart. The degradation effect is mainly by absorption, and when absorption reaches saturation point, take the composite material out in the sunshine for the regeneration of absorbent. At last, we use various kinds of absorbent (active carbon fiber, granular active carbon and silicon dioxide aerogel) combine with visible light nanometer TiO₂ for degradation experiment of formaldehyde as reprentative of VOCs.