Adsorption isotherms of p-nitrpphenol from its solutions on two sample of activated fibers and two samples of granulated activated carbons have determind in the concentration range 40-800mg/L(ppm). The surface of these carbons was modified by oxidation with nitric acod oxygen gas, and by degassion the carbon surface under vacuum ay temperture of 400 ℃. 650 ℃ and 950 ℃. The oxidation of carbon enhances the amount of carbon-oxygen surface groups, while degassing decreases the amount of these surface groups.