Activated carbon from irish potato peels, treated with H3PO4 and ZnCl2 were prepared using the one and two stage processes. The study was designed to model the adsorption of a dye, methylene blue, using the Freundlich isotherm model. Both acid and salt catalyzed carbon presented favorable adsorption, with Freundlich constant values, n < 1. The adsorption capacities (k), intensities (1/ n) and correlation (R2) values for the applicability of the model all compared favorably well with those of reference commercially available activated carbon.
Key words: Freundlich, activated carbon, adsorption intensities, adsorption capacities, Irish potato.