Kinetics of adsorption of pharmaceutical substances from aqueous solutions on activated carbons

Abstract

The article has investigated regularities of adsorption of sulfanilamide, sulfathiazole, procaine, levamisole and caffeine on activated carbons of various porous structure. The adsorption rate of substances diminishes in the series sulfanilamide > caffeine > procaine > sulfathiazole > levamisole and decreases with an increase of the fraction of micropores in the structure of sorbents. It was found that at the degree of using the adsorption capacity of the sorbent of up to γ = 0.5–0.6 the kinetics of adsorption satisfactorily is described by means of an external diffusion model. The use of 50% of sorption capacity of activated carbon is achieved over ~ 10% time necessary for establishing adsorption equilibrium.