In a previous study, H-bonding was postulated as a mechanism of adsorption for aromatics on oxygen-containing activated carbon. To verify this, the adsorption of phenol, aniline, benzene, and nitrobenzene was studied as a function of surface oxygen groups. It was determined that there is a linear correlation between total surface acidity and adsorption capacity for H-bonding adsorbates in cyclohexane. Flow microcalorimetry (FMC) and ultrasonic desorption tests also indicate stronger and less reversible adsorption bonds for H-bonding adsorbates. Reversibility of adsorption decreased with increasing surface oxygen concentration, indicating a strong relationship between the oxygen groups and adsorption mechanism.

Separation Science and Technology, Volume 39, Issue 1 January 2005 , pages 43 - 62