ANALYSIS OF A THIN ACTIVATED CARBON LOADED ADSORPTION MEDIUM

Thin adsorption media are being investigated for use in a variety of a pplications including protective clothing for military use and hazardo us waste cleanup, as well as in indoor air quality within a variety of filtration media. The objective of this study was to evaluate the dyn amics of adsorption of a chlorinated organic gas on activated carbon i mpregnated meltblown laminates. The adsorption data were collected on a bench scale test stand on an existing battle dress overgarment and a n experimental activated carbon impregnated liner material for use in protective clothing. Activated carbon loadings were nominally 40, 80, and 120 g/m(2). This paper reviews the results of the study and compar es the experimental results to existing adsorption theory. For the org anic compound, trichloroethylene, which was studied, a favorable isoth erm was found. Although the materials were thin, the media provided a finite breakthrough, defined as a 1% penetration, followed by a gradua l breakthrough curve similar to those typically observed in thicker be d adsorption systems. Adsorption isotherms were developed for the acti vated carbon loaded laminates; the isotherms were of the Freundlich ty pe. A conventional thick bed adsorption model was used to simulate and compare to the results obtained on the activated carbon loaded lamina tes. Unlike conventional activated carbon beds where the width of the breakthrough curve is a relatively small portion of the bed depth, the breakthrough curves for these thin laminates comprised a significant portion of the bed depth resulting in breakthrough capacities which we re substantially less than the overall absorption capacity of the lami nates.