OLS : Record


Main Title Sorption and Reemission of Formaldehyde by Gypsum Wallboard.
Author Chang, J. C. S.;
CORP Author Environmental Protection Agency, Research Triangle Park, NC. Air and Energy Engineering Research Lab.
Publisher 1993
Year Published 1993
Report Number EPA/600/A-93/078;
Stock Number PB93-180917
Subjects Formaldehyde; Indoor air pollution; Sorption; Desorption; Mathematical models; Mass transfer; Wallboard; Construction materials; Buildings; Gypsum; Insulation; Study estimates; Comparison;
Library   Call Number Additional Info Location Date Modified
NTIS PB93-180917 Most EPA libraries have a fiche copy filed under the call number shown. Check with individual libraries about paper copy. NTIS 08/23/1993
Collation 25p
Abstract The paper gives results of an analysis of the sorption and desorption of formaldehyde by unpainted wallboard, using a mass transfer model based on the Langmuir sorption isotherm. The sorption and desorption rate constants are determined by short-term experimental data. Long-term sorption and desorption curves are developed by the mass transfer model without any adjustable parameters. Compared with other empirically developed models, the mass transfer model has more extensive applicability and provides an elucidation of the sorption and desorption mechanism that empirical models cannot. The mass transfer model is also more feasible and accurate than empirical models for applications such as scale-up and exposure assessment. For a typical indoor environment, the model predicts that gypsum wallboard is a much stronger sink for formaldehyde than for other indoor air pollutants such as tetrachloroethylene and ethylbenzene. The strong sink effects are reflected by the high equilibrium capacity and slow decay of the desorption curve.
Supplementary Notes See also PB88-251657 and DE86012632. Presented at the ASHRAE IAQ '92 Conference, San Francisco, CA., October 18-21, 1992.
NTIS Title Notes Rept. for Jun 90-Aug 92.
Category Codes 68A; 89G
NTIS Prices PC A03/MF A01
Primary Description 600/13
Document Type NT
Control Number 317523621
Cataloging Source NTIS/MT
Origin NTIS
Type CAT