Abstract
The diffusion coefficient (D m) and material/air partition coefficient (K) are two key parameters characterizing the formaldehyde and volatile organic compounds (VOC) sorption behavior in building materials. By virtue of the sorption process in airtight chamber, this paper proposes a novel method to measure the two key parameters, as well as the convective mass transfer coefficient (h m). Compared to traditional methods, it has the following merits: (1) the K, D m and h m can be simultaneously obtained, thus is convenient to use; (2) it is time-saving, just one sorption process in airtight chamber is required; (3) the determination of h m is based on the formaldehyde and VOC concentration data in the test chamber rather than the generally used empirical correlations obtained from the heat and mass transfer analogy, thus is more accurate and can be regarded as a significant improvement. The present method is applied to measure the three parameters by treating the experimental data in the literature, and good results are obtained, which validates the effectiveness of the method. Our new method also provides a potential pathway for measuring h m of semi-volatile organic compounds (SVOC) by using that of VOC.
Highlights
Indoor air pollution from formaldehyde and volatile organic compounds (VOC) is known to pose an adverse threaten to human health [1,2,3]
Building materials, which have been acknowledged as major formaldehyde and VOC sources in indoor environment, there is evidence that it can affect the transport and removal of the pollutants by sorption and desorption, i.e., reducing the peak concentration while prolonging the presence
One of the main merits of this model lies in that, the characteristic parameters used by this model, that is, the diffusion coefficient (Dm), and the material/air partition coefficient (K), are the physical properties of the material-VOC pairs, which can be obtained by independent experiment
Summary
Indoor air pollution from formaldehyde and volatile organic compounds (VOC) is known to pose an adverse threaten to human health [1,2,3]. For the characterization of formaldehyde and VOC sorption in building materials, two general physical models are used, i.e., the first order adsorption/desorption rate model and the equilibriuminterface model [9,10,11,12,13,14,15,16,17]. Cox et al proposed a microbalance method to obtain K and Dm [19] For this method, K is pre-determined by sorption experiment in ventilated chamber and Dm is subsequently determined by fitting the experimental data to a mathematical model. Li and Niu [21] proposed an inverse method to simultaneously determine the Dm and K by non-linearly fitting the experimental data to Deng and Kim’s model [22] with known initial emittable concentration and convective mass transfer coefficient. There is still a challenge to determine the Dm and K based on the sorption process in airtight chamber
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call