Production of Activated Carbon from Palm-oil Shell by Pyrolysis and Steam Activation in a Fixed Bed Reactor

Abstract

The research objective was to produce activated carbon from palm-oil shells by one step pyrolysis and steam activation in a fixed bed reactor with the diameter of 100 mm. The studied variables were activation temperature, activation time, palm-oil shell sizes and flow rate of air. The results showed that the optimum condition was 1.18-2.36 mm of palm-oil shells at 750oC for 2 hr with air flow rate of 0.72 nl/min, using steam as an activating agent. The characteristics of the prepared activated carbon with the yield of 19.66 % were bulk density of 0.5160 g/cm3, 6.03 % ash, iodine number of 620.16 mg/g, methylene blue number of 176.75 mg/g and 559.48 m2/g of BET surface area. In addition, it had been found that when there was an addition of pyrolysis time with air before steam activation led to higher porosity development than one step pyrolysis and steam activation. From these experimental data, it was observed that the maximum surface area and adsorption capacity could be obtained from using 200 g of 1.18-2.36 mm of palm-oil shells at 750oC for 3 hr by addition pyrolysis with air for 30 min (0.72 nl/min) before steam activation. The resulting characteristics of the final product with the yield of 12.18 % were bulk density of 0.5048 g/cm3, 7.54 % ash, iodine number of 766.99 mg/g, methylene blue number of 189.20 mg/g and 669.75 m2/g BET surface area.