Impact of Temperature on the Ratio of Initial Emittable Concentration to Total Concentration for Formaldehyde in Building Materials: Theoretical Correlation and Validation

Abstract

The initial emittable concentration (Cm,0) is a key parameter characterizing the emission behaviors of formaldehyde from building materials, which is highly dependent on temperature but has seldom been studied. Our previous study found that Cm,0 is much less than the total concentration (C0,total, used for labeling material in many standards) of formaldehyde. Because Cm,0 and not C0,total directly determines the actual emission behaviors, we need to determine the relationship between Cm,0 and C0,total so as to use Cm,0 as a more appropriate labeling index. By applying statistical physics theory, this paper derives a novel correlation between the emittable ratio (Cm,0/C0,total) and temperature. This correlation shows that the logarithm of the emittable ratio multiplied by power of 0.5 of temperature is linearly related to the reciprocal of temperature. Emissions tests for formaldehyde from a type of medium density fiberboard over the temperature range of 25.0-80.0 °C were performed to validate the correlation. Experimental results indicated that Cm,0 (or emittable ratio) increased significantly with increasing temperature, this increase being 14-fold from 25.0 to 80.0 °C. The correlation prediction agreed well with experiments, demonstrating its effectiveness in characterizing physical emissions. This study will be helpful for predicting/controlling the emission characteristics of pollutants at various temperatures.

A prediction model of VOC partition coefficient in porous building materials based on adsorption potential theory

“…Four types of macro-mesoporous materials commonly used in indoor decoration were selected as the subjects of the formaldehyde emission experiments conducted by the CTR-VVL method. The experimental data of C m0 of the four materials showed a good consistency with the theoretical correlation in the literature [37]. The relational expressions of K varying with temperature were obtained by fitting the experimental data of K with the theoretical calculation model, which can predict the K under different temperatures.…”

“…This combined effect caused accelerated emission rates and higher equilibrium concentrations with the increasing temperature. Huang et al [37] derived a theoretical correlation between C m0 and temperature for formaldehyde emissions as follows:…”

Understanding and controlling airborne organic compounds in the indoor environment: mass transfer analysis and applications

“…The initial emittable concentration of formaldehyde ( C 0 ) in building material has been found to be much lower than the concentration measured by the perforator method ( C total ) at room temperature (Wang and Zhang, ), and C 0 changes with environmental conditions particularly temperature (Xiong and Zhang, ). These phenomena are preliminarily explained by statistical physics (Huang et al., ). From the microscopic perspective, formaldehyde molecules are bonded to the material surface by adsorption, and a molecule is emittable only when the kinetic energy of this molecule is high enough to overcome the bonding forces, that is, to overcome an energy barrier.…”

Preparation and characterization of cysteine‐formaldehyde cross‐linked complex for CO2 capture

“…The potential health consequences of formaldehyde are serious concerns, such as poisoning, carcinogenic, and teratogenic function . Although a series of standards to regulate formaldehyde have been implemented, the lack of enforcement has resulted in limited success in controlling exposures from environmental, occupational, residential, and contaminated food sources . Even so, the quantity and quality of studies on formaldehyde controlling exposures still remain limited; to date, there have been few designed studies on formaldehyde removal for highly valuable by‐products from various exposure sources to protect human health, not just in China but also all over the world.…”

“…[1][2][3] Although a series of standards to regulate formaldehyde have been implemented, the lack of enforcement has resulted in limited success in controlling exposures from environmental, occupational, residential, and contaminated food sources. [4][5][6] Even so, the quantity and quality of studies on formaldehyde controlling exposures still remain limited; to date, there have been few designed studies on formaldehyde removal for highly valuable by-products from various exposure sources to protect human health, not just in China but also all over the world. Although photo-catalytically eliminating formaldehyde under ultraviolet or visible light, [7][8][9][10][11][12] and various adsorption disposals, [13][14][15][16][17][18] have been widely investigated, these processes presented some potential problems, such as possibly producing CO due to incomplete treatment, which limited their practical application.…”