Chemically Activated Carbon for the Adsorption of Aniline from Water

Abstract

The adsorption of aniline from aqueous solution on carbon sorbents is investigated. The sorbents are derived from D and G Kuznetsk Basin coal by chemical activation using potassium hydroxide at 800°C, when the coal/alkali ratio (by mass) is 1.0 : 0.5 and 1.0 : 1.0. The sorbents consist mainly of micropores, and their specific surface is relatively high (700–1340 m²/g). The experimental adsorption isotherms are plotted. On that basis, the parameters of the Langmuir, Freundlich, Dubinin–Astakhov, and BET sorption models are calculated. The models are appropriate for the description of aniline adsorption (R² > 0.9). The Langmuir model is the most accurate. The state parameters indicate that the adsorption of aniline by this means is very effective. The process may be described as monomolecular adsorption on the surface of microporous sorbents. The thermomechanical characteristics of the adsorption process are low. That indicates physical adsorption.