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The paper presents results of a study on obtaining activated carbon from common corn cobs and on its use as adsorbent for removal of pollution from liquid and gas phases. The crushed precursor was subjected to pyrolysis at 500 and 800°C in argon atmosphere and next to physical or chemical activation by CO 2 and KOH respectively. The effect of pyrolysis conditions and activation method on the physicochemical properties of the materials obtained was tested. The sorption properties of the carbonaceous adsorbents obtained were characterized by determination of nitrogen dioxide and hydrogen sulphide sorption from gas stream in dry and wet conditions as well as by iodine and methylene blue removal from aqueous solution.The final products were microporous activated carbons of well-developed surface area varying from 337 to 1213 m 2 /g and showing diverse acid-base character of the surface. The results obtained in our study have proved that a suitable choice of the activation procedure for corn cobs permits production of cheap adsorbents with high sorption capacity toward toxic gases of acidic character as well as different pollutants from liquid phase.

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A technology of obtaining nitrogen-enriched activated carbons from coniferous tree sawdust by direct activation of the precursor and physical activation with CO 2 is described. The effect of activation time, pyrolysis temperature as well as modification with urea on the textural parameters, acid-base character of the surface and sorption properties of activated carbons has been tested. The resulting carbons were characterised by low-temperature nitrogen sorption and determination of the number of surface oxygen groups. The sorption properties of the materials obtained were characterised by nitrogen dioxide adsorption in dry and wet conditions. The final products were nitrogen-enriched microporous activated carbons of medium-developed surface, showing very diverse nitrogen content and acidic-basic character of the surface. The results obtained in our study have proved that through suitable choice of the activation and modification procedure of coniferous tree sawdust, activated carbons can be produced with high capacity towards nitrogen dioxide adsorption, reaching to 69 and 46 mg NO 2 /g in dry and wet conditions, respectively. The results of our study have also shown that the adsorption ability of carbonaceous adsorbents depends both on the method of preparation as well as on the textural parameters and acid-base properties of the adsorbents surface.