Photocatalytic Oxidation for Maintenance of Indoor Environmental Quality

Abstract

The purpose of this paper is to provide a review of the application of photocatalytic oxidation (PCO) techniques for reduction of indoor air pollutants to assess feasibility for their application in air-tight zero-carbon housing. Due to emissions from building materials, such as coatings and wood-based materials on walls, ceiling and floors, as well as other furnishing materials such as new floor covering, there will always be high concentrations of volatile organic compounds (VOCs) in the indoor air of a newly completed building, especially air-tight homes. The concentrations could be reduced by the use of low emission products; however, PCO could further reduce the risk of emissions of these VOCs including formaldehyde. The use of PCO could also reduce risks caused by other indoor pollutions such as NOx, CO, CO2, moisture and microbes. The mechanism and applications of PCO reactors such as titania incorporated onto material surfaces of various built environments (roads, building façade and interior); and in HVAC systems for maintenance of indoor environmental quality, especially indoor air quality (IAQ) are discussed in the review as well as discussion on performance. The effects of temperature and moisture and possible toxic effects of PCO on environment are also included for consideration.