In this study, activated carbons were prepared from sugar beet bagasse, which is side product and waste in sugar plants, by chemical activation with ZnCl2. Influence of activation temperature was investigated on to pore structure. ZnCl2/sugar beet bagasse ratio (impregnation ratio) was selected as 1: 1. The impregnated sample was raised to the activation temperature under N-2 (100 ml/min) atmosphere with 10 degrees C/min heating rate and hold at this temperature for 1 h. The activation temperature was varied over the temperature range of 400-900 degrees C. BET surface area values were determined in the range of 832-1697 m(2)/g. Under the experimental conditions, 500 degrees C was found to be the optimal condition for producing high surface area carbons with ZnCl2 activation. Sugar beet bagasse was suitable for preparation of activated carbon with essentially microporous structure. Activated carbon ash content was found in the range of 1.2-2.7 (%w/w d.b.). Activated carbon samples and raw material were characterized by XRD, FT-IR, DTA and TGA. (c) 2006 Elsevier B.V. All rights reserved.