Adsorption of Benzene and Phenolic Derivatives in Monolithic Carbon Aerogels

Abstract

A monolithic carbon aerogel with a specific pore texture was used as benzene adsorbent. Adsorption was carried out under static conditions at 25 o C and at saturation, an adsorption capacity as high as 0.77 cm 3 .g �1 or 837 mg.g �1 was obtained. This work is devoted to the application of carbon aerogels for the removal of hydroquinone, catechol and resorcinol from aqueous solutions. These materials were tested and characterised regarding their morphology, particle size distribution, surface area and porous structure. Equilibrium tests were carried out at different adsorbate concentrations and the experimental data were correlated by means of Langmuir and Freundlich isotherms. The equilibrium data were well described by Langmuir and Freundlich in most cases. The maximum adsorption capacity of the Langmuir model was observed for the adsorption of benzene onto aerogel (242.33 mg/g), though the most promising results were obtained for toluene adsorption, owing to the greater adsorption energy involved. Comparing these results with other reported results, our carbon aerogel hydrophobics were found to exhibit a remarkable performance for the removal of benzene.