Preparation and characterization of the activated carbon from the coconut shell using the combination of both chemical and physical activations with the activator of KOH and CO2 stream has been conducted. The research was aimed to study the mechanism of chemical change that occurred during the activation process by characterizing the charcoal after being chemically and physically activated. The coconut shell charcoal was immersed in the solution of KOH (0.5-2.0 M) for 12-24 h. It was then activated on the activation reactor at 800 °C with the stream of CO2 20 mL/min and with the variation of time 30-150 min. Characterization of the activated carbon included FT-IR, SEM and specific surface area BET analyses. FTIR analysis showed that the surface of the activated carbon had the functional group of O-H, C-H, C=C, and C-O. SEM analysis showed that the activated carbon had more porous structure. In addition, the pore diameter increased by the increasing of the activation time. The best activated carbon was obtained with the condition of KOH 2 M, immersion time of 24 h, activation time of 120 min. At such condition, the obtained activated carbon had properties of surface area BET of 451,14 m2g-1, pore volume of 2,506 x 10-1 cm3g-1 and the averaged pore radius of 11,109 Ǻ.
