Adsorption characteristics of trace volatile organic compounds in gas streams onto activated carbon fibers

Journal Article · · Chemistry of Materials; (United States)

DOI:https://doi.org/10.1021/cm00023a026· OSTI ID:5115116

Foster, K L; Fuerman, R G; Economy, J; Larson, S M; Rood, M J ^[1]

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1. Univ. of Illinois, Urbana, IL (United States)

The adsorption characteristics of activated carbon fibers (ACF) prepared from phenolic precursors were examined. Three ACF with specific surface areas of 900, 1610, and 2420 m[sup 2]/g were used to determine the adsorption of volatile organic compounds (VOC) over a range of concentrations in air or nitrogen gas streams. Gravimetric adsorption was used both to determine the ACF effective pore volume using several individual VOC saturated in nitrogen or air at atmospheric pressure and to determine adsorption isotherms of n-butane over a large range of concentrations (49.8 ppmv to 99.5 vol%) in nitrogen at atmospheric pressure and 25[degrees]C. The experimental results showed that while for saturated adsorption results, where adsorption increased with increasing ACF specific surface area, at lower concentrations the ACF with the least specific surface area absorbed more. This low concentration reversal was also observed with acetone (10.3 ppmv) in air and benzene (56.5 ppmv) in nitrogen. The authors conclude that this isotherm crossover results from the ACF activation process where the micropores are widened (and the specific surface area concomitantly increased) with increasing activation duration and that this crossover is in agreement with predictions of the Dubinin-Radushkevich equation. These results are important for the development and design of materials for low concentration adsorption applications such as maintaining and improving ambient air quality.

• OSTI ID: 5115116
• Journal Information: Chemistry of Materials; (United States), Journal Name: Chemistry of Materials; (United States) Vol. 4:5; ISSN CMATEX; ISSN 0897-4756
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
54 ENVIRONMENTAL SCIENCES
540120 -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (1990-)
ADSORPTION
ALKANES
BUTANE
CARBON FIBERS
FIBERS
HYDROCARBONS
MATTER
ORGANIC COMPOUNDS
PHYSICAL PROPERTIES
SORPTION
SORPTIVE PROPERTIES
SPECIFIC SURFACE AREA
SURFACE PROPERTIES
VOLATILE MATTER