Experimental Study and Modeling of the Photocatalytic Oxidation of NO in Indoor Conditions

QINGLIANG YU; JOS H.J.H. BROUWERS; MARÍA DE LOS MILAGROS BALLARI

Praga (República Checa)

Simposio; 3rd International Symposium on Nanotechnology in Construction; 2009

With the use of Nano-material like TiO2 as photocatalyst, heterogeneous photocatalytic oxidation has shown to be a promising air purifying technology. Nitrogen monoxide (NO) is one common indoor air pollutant. Gypsum plasterboard is used widely as construction material because of its superior fire resistance property. The present paper addresses the photocatalytic degradation of NO in indoor conditions with the application of gypsum plasterboard as a special substrate and carbon-doped TiO2 as photocatalyst. The modified photocatalytic reaction setup is introduced for the assessment of the indoor air quality. The photocatalytic degradation experiments were carried out with the NO as target pollutant under visible light irradiance and the photocatalytic degradation rate of NO under different experimental conditions is investigated. The photocatalytic effect of the carbon-doped TiO2 is evaluated with the different light wavelength ranges from UVA light to visible light. The influence of the reactor volume on the photocatalytic degradation rate is studied. The photocatalytic reaction mechanism is investigated. The Langmuir-Hinshelwood (L-H) model is applied to describe the photocatalytic reaction mechanism and experimental results show the validity of the L-H model in the present research. A mathematical expression is proposed to describe the reaction process in the reactor. The present model allows the different initial NO concentration, the different reactor volume, and the different volumetric flow rate of the target pollutant. The influence of other experimental conditions like relative humidity and light intensity on the L-H model is discussed as well.