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The effects of modification by HNO3 oxidization on the physico-chemical properties of activated carbon fiber (ACF), the adsorption of aniline, pyridine and phenol on ACF and modified ACF, as well as the influence of textural properties on adsorption by comparing ACF with an activated carbon are investigated. The adsorbents are characterized using N2 adsorption, Boehm titration, diffuse reflectance infrared Fourier transform spectroscopy, and temperature-programmed desorption. The pore properties of ACF are not significantly changed by the modification; however, it increases greatly the oxygenated acidic groups on the surface of ACF. The uptake for each aromatic compound by the modified ACF is lower than on ACF. This is mainly due to the decrease of dispersive interaction, more water cluster formed to block entry of compounds into micropores or competition between water and compounds adsorbed onto the surface of ACF because of hydrophilic increase of ACF. The maximum uptake for the aromatic compounds decreases with the increase in aqueous solubility of the adsorbates. K, a Langmuir parameter, is indirectly associated with the surface chemistry of ACF. For the aromatic compounds mentioned, the uptake increases with the micropore volume of carbon materials.

The adsorption and de-sorption properties of polycyclic aromatic hydrocarbons (PAH) which was represented by pure phenanthrene, on activated carbon were investigated. The influences of solvent (acetone,carbon tetrachloride, tetrahydrofuran, ethanol or distilled water), time and manner (with ultrasonic or not) on the desorption efficiency were investigated. The results show that the de-sorption efficiency reaches 91.40% which exhibits the highest efficiency when the ethanol is used as the de-sorption solvent and the system was treated with ultrasonic technology. The desorption test was also carried on the raw coconut shell-based activated carbon and it was not being used before. This determination is to understand the “baseline background” and the purity of raw activated carbon characteristics. The content of total de-sorption amounts was 0.043% of raw activated carbon. Through GC/MS analysis,the main desorption substance defined was 10-undecenoic acid methyl ester.