The aim of this work is to gain a better fundamental understanding of the nature of surface oxide sites present on carbon surfaces, and their role in the adsorption process. A number of model carbon substrates with diffeent degrees of surface oxidation and similar textural properties were prepare using a wide range of solution and gaseous phase oxidatin techniques. Some of the carbons were characterised using established tehcniques including flow microscalorimetry, thermogravimetric analysis (TGA) and X-ray photoelectron spectroscopy (XPS). The resutls showed that both carboxylic acid (-CO_2H) and ether/hydroxyl (C-O) surface oxygen compelxes were introduced to all of these carbons as a result of the oxidation processes. The number, strength and thermal stability of the surface groups formed were dependent on the nature of the base material and the oxidtion conditions employed. The dynamci adsorption performance of the carbons against hexane, under humid conditions, was found to be mainly determined by the quantity of acidic surface functinal groups. However, the location, strength of interactin and availability of the surface oxygen compelxes to the adsorbate molecules, are also thought to affect the breakthrough characteritics of the carbons used in this work.
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