Sorption Isotherms of Acetone on Various Building Materials

Abstract

The physical modelling of Indoor Air Quality (IAQ) suffers a lack of sorption data for the most common Volatile Organic Compounds (VOC) on building materials. This paper deals with an experimental facility that aimed to provide the sorption isotherms of gaseous contaminants on various materials. It was used to determine the sorption isotherms of acetone on chipboard, acrylic paint, and the gypsum core of commercially available gypsum board. After a brief introduction to fundamental principles of sorption, the experimental device is presented in detail. The results are reported and discussed, emphasising the description of the isotherm shapes and the possible partial reversibility of the sorption phenomenon for porous materials. The resulting curves are clearly non linear when dealing with gypsum and chipboard. Moreover, the sorption isotherms of acetone on gypsum were found to be different whether they were determined in the directions of increasing or decreasing concentrations. Many questions remain unresolved about the physico-chemical processes involved, the sorption data to be considered for the purposes of IAQ modelling, and the way to account for the observed phenomenon when modelling the sorption/diffusion contaminant transport in building materials.

A Novel Method for Measuring the Diffusion, Partition and Convective Mass Transfer Coefficients of Formaldehyde and VOC in Building Materials

“…As far as the measurement of D m and K is concerned, many kinds of methods have been proposed by virtue of sorption or emission test in environmental chambers, which can measure the D m and K respectively or simultaneously. Tiffonnet et al put forward a multi-sorption method to determine K [18]. Cox et al proposed a microbalance method to obtain K and D m [19].…”

Physically Based Modelling of the Material and Gaseous Contaminant Interactions in Buildings: Models, Experimental Data and Future Developments

“…As shown in Table 3.2, it results in a 41, 53 and 28 per cent decrease in the absorption coefficient when the temperature is increased from 25°C to 35°C. Tiffonnet et al (2002) found a lower heat of absorption of -7.5 kJ/mol for acetone in acrylic paint, reflecting slighter changes in K H with temperature (see Table 3.2). Finally, still based on the results of Tiffonnet et al (2002), the acetone heat of adsorption in particle board would have a value of about -30 kJ/mol -that is to say, the same order of magnitude as typical heats of absorption in polymers.…”

“…Tiffonnet et al (2002) found a lower heat of absorption of -7.5 kJ/mol for acetone in acrylic paint, reflecting slighter changes in K H with temperature (see Table 3.2). Finally, still based on the results of Tiffonnet et al (2002), the acetone heat of adsorption in particle board would have a value of about -30 kJ/mol -that is to say, the same order of magnitude as typical heats of absorption in polymers. However, there is too little data to draw definitive conclusions on the compared temperature sensitivity of K p and K H .…”

“…Indeed, newly manufactured materials often exhibit pore-phase VOC concentrations that are several orders of magnitude higher than those commonly found in indoor settings. Within this concentration range, the adsorption isotherm may show non-linearities, as shown by Tiffonnet et al (2002) when dealing with the emission of acetone from particle board. Practically, sorption parameters have been determined in the context of characterizing either the sink or source behaviour of building materials.…”

Material Emissions and Indoor Simulation

“…Recently particularly in Japan, there has been a lot of interest in the use of sorptive building materials to reduce the concentrations of VOCs and formaldehyde in indoor environments [57][58][59][60][61][62][63][64][65][66]. The mass transfer coefficients, material loading and air change rate can influence the sorptive behaviour, particularly in respect to formaldehyde concentration in air [58,67].…”