Sorption behaviour of volatile organic compounds on material surfaces - The influence of combinations of compounds and materials compared to sorption of single compounds on single materials

The sorption of volatile organic compounds (VOC) on material surfaces was evaluated by chamber testing. The sorption of single VOCs was compared to the sorption of the combination of the VOCs and the sorption of single material surfaces was compared to the sorption of the combination of material surfaces. The sorption compounds were alpha-pinene and toluene, and the material surfaces were wool carpet and nylon carpet. The sink effect of the chambers and the effect of the loading of the materials were evaluated separately. The results show that the loading has no influence by itself. Relatively high loading minimises the sink effects of the test chamber and is therefore recommended. The presence of two chemical compounds at the same time gives correspondingly higher sorption compared to experiments with one compound at a time. The results indicate that the desorbed masses of individual compounds are additive, making prediction of the desorbed mass of combinations of compounds possible. The combination of two materials at the same time leads to higher sorption than one single material. The results indicate that the effect was additive, even if the results for alpha-pinene are not completely clear. There is a need for further research to investigate the sorption behaviour of combinations of materials as well as other combinations of common indoor compounds. A one-sink model, based on a linear Langmuir adsorption isotherm, appears adequate to describe the results, (C) 1999 Elsevier Science Ltd.