Gravimetric Studies on VOC Adsorption by Indoor Materials under Near-Ambient Conditions

Adsorption and desorption of volatile organic com pounds (VOCs) by indoor materials can have a signifi cant impact on indoor air quality. Investigations with oth er environmental matrices than building materials have shown that the presence of water has a strong impact on VOC adsorption. The purpose of the present study was to develop and validate a microbalance set-up aimed at investigating VOC adsorption by indoor materials under controlled relative humidity at ambient pressure. The experimental set-up is described and the adsorption iso therms and partition coefficients obtained for combina tions of m-xylene and n-octane with several indoor mate rials are reported. Linear or almost linear adsorption iso therms were found for most combinations of com pounds and materials. n-Octane is in all cases less strongly adsorbed than m-xylene. Comparison with data originating from a different experimental technique gave acceptable agreement between the methods for most of the materials tested.