Assessment of the indoor air purification by photocatalytic paints

Abstract

Photocatalytic building materials con-taining TiO2 were extensively studied for outdoor ap-plications using solar radiation. Nowadays, the mar-ket offers a wide variety of these materials with self-cleaning and air purification functionalities. How-ever, heterogeneous photocatalysis applied in indoor construction materials was less developed. The objec-tive of this work is to investigate the photocatalytic performance of carbon doped TiO2 in replacement of the normal pigments in indoor wall paint formula-tions. To achieve this goal, the photocatalytic oxida-tion of acetaldehyde in gas phase was carried out. The air decontamination process was conducted using regular indoor light in a bench scale chamber photo-reactor simulating a room. The main environmental conditions that affect the photocatalytic process were varied: air flow rate, irradiance, relative humidity and acetaldehyde concentration. The results were an-alyzed through the response surface methodology and revealed the air purifying power of photocatalytic paints under indoor conditions.