PH21 Homeland Security: Agents, Detection, and Emergency Response
Exhibit Hall
8:00 AM - Thursday, 13 November 2003
(PH183) Adsorption studies on chemical warfare protective substrates.
Sata, U1, Ramkumar, S2, 1 The Institute of Environmental and Human Health - Texas Tech University, Lubbock, Texas, USA2 The Institute of Environmental and Human Health - Texas Tech University, Lubbock, Texas, USA
ABSTRACT- Barrier protective and breathable chemical protective fabrics provide necessary protection against toxic chemicals and chemical warfare agents (CWA). In order to maximize the barrier efficiency the composite material is designed in a way that it is composed of at least three layers: 1. Pre-filter layer; 2. Middle adsorbent layer; 3. Next-to-skin layer. The critical properties of the middle adsorbent layer are its specific surface area, effective pore volume, weight, spatial distribution, adsorption rate and adsorption capacity. The purpose of this study is to perform a qualitative comparison between three different activated carbon fabrics (ACF ′ s) and the composite fabrics developed using these ACF ′ s. ACF ′ s with same specific surface area of 2500 m2/g but different mass per unit area and woven constructions [92 g/m2(plain weave) and 137 g/m2(basket weave)] were used to determine the adsorption of toxic chemicals in nitrogen gas stream. These results were then compared with the adsorption of toxic chemicals using ACF with surface area of 1500 m2/g. A final comparison between the adsorption by the ACF ′ s and the adsorption by their composites is presented in a graphical representation. A high precision thermo-gravimetric analyzer (Pyris 1 TGA Perkin Elmer) was used to best describe the increase in weight of the ACF ′ s and the composite fabrics with time to study dynamic adsorption. The characteristic adsorption isotherms for the three activated carbon fabrics and their composites were compared for factors such as the rate of adsorption for a specific time interval, saturation time and adsorption capacity.
Key words: activated carbon fabrics, chemical protective fabrics, chemical warfare, protective suits