Abstract: Activated carbon with decolorization capability to caramel was prepared from Yilan coal by activation with water vapor. When the yields of carbonization and activation were respectively 74.0%-76.2% and below 14.0%, the adsorption properties of prepared activated carbon were: methylene blue 232.5 mg/g, decolorization to caramel B 80%, and better decolorization capability to colorful aqueous solution in comparison with reference material of activated carbon. Ash and other impurities in activated carbon could be reduced to meet the requirements for the decolorization of colorful aqueous solution by a simple and effective method. The activation technique and some problems occurred during activation process were discussed. It was found that the decolorization capability of prepared activated carbon was increased by prolonging activation time at activation temperature of 860℃, but the activation yield was reduced at the same time.

Key words: Yilan coal, activated carbon, water vapor activation, decolorization