Adsorption of Biologically Active Compounds from Aqueous Solutions on to Commercial Unmodified Activated Carbons

Abstract

The paper describes work associated with the continued investigation of the adsorption of paracetamol from aqueous solution at neutral pH. Using previously described carbons, some additional measurements, i.e. FT-IR spectroscopy and XPS, were performed to characterise the chemical composition of the surface. The results of batch-reactor-test kinetic measurements performed at different temperatures (300, 310 and 320 K) are presented and were described using two simple equations. The influence of carbon sieving and surface acidity on the kinetics of paracetamol adsorption is also discussed. The values of the diffusion coefficients (D e ) were calculated and a mechanism of diffusion is proposed. It is shown that if carbon samples possess a similar porosity, the values of D e for paracetamol are higher for diffusion in the pores of the material possessing a more hydrophilic surface, i.e. for that carbon for which the higher value of the enthalpy of immersion in water was obtained.