MadSci Network: Chemistry |
Gaseous samples can be analysed by accumulating the possible compound on a solid phase. The mechanism for this is called adsorption, quite different from absorption, as it happens on the surface. The solid phase can be left "as is" in a room or, helped by an air pump, forcing air through the solid phase. [1] Subsequent analysis of the adsorbed substances can be performed via gas chromatography (GC), just by heating the solid phase and releasing the adsorbed substances into the GC or dissolving these in another organic solvent such as carbon disulphide (CS2), and this solution injected into the GC [2,3] The solid phase commonly used for general purposes is Tenax [4], but charcoal is specially good for volatile organic compounds, Anasorb 747 for polar compounds and DNPH for ketones and aldehydes [5,6] [1] Fifield, Kelley. Principles and practice of analytical chemistry. 5th Ed. [2] Skoog, Holler, Nieman. Principals of instrumental analysis. 5th Ed [3] Skoog, West Holler, Crouch. Fundamentals of Analytical Chemistry. 8th Ed. [4] http://www.sisweb.com/index/referenc/tenaxtam.htm [5] http://www.brumi.de/Literatur/173_Tenax_Absorption_2002.pdf [6] http://www.et1.tu-harburg.de/downloads_et1/umt/publikationen/tenax.pdf
Try the links in the MadSci Library for more information on Chemistry.