EFFECT OF CARBONIZATION TEMPERATURE ON PROPERTIES OF CHAR AND ACTIVATED CARBON FROM COCONUT SHELL
Keywords:
Coconut shell chars, carbonization, activated carbon, porous propertiesAbstract
This research focused on investigating the effect of the carbonization temperature on the porousproperties (surface area, pore volume, and mean pore size) of coconut shell based activated carbon prepared by physical activation with carbon dioxide. The carbonization temperature was varied in the range from 250-750oC and the derived chars were activated in CO2 at 850oC for 60 and 120 min. The porous properties of the activated carbons obtained including the Brunauer-Emmett-Teller (BET) surface area, pore volume, pore size distribution, and average pore diameter were determined by nitrogen adsorption isotherms at -196oC. The experimental results showed that most pores occurred during the activation predominantly as micropores with a small proportion of mesopores. The porous properties of the activated carbon decreased with the increase in the carbonization temperature,with the char prepared at the lowest carbonization temperature of 250oC and activated at 850oC for 120 min giving activated carbon with the highest BET surface area and pore volume of 1056 m2/g and 0.533 cm3/g, respectively. From the obtained results, it is feasible to produce activated carbon with high porous properties from coconut shell by selecting the appropriate conditions for the carbonization and activation steps.
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