Production of activated carbon from peanut hill using phosphoric acid and microwave activation

Abstract

The optimum conditions for preparing activated carbon from peanut hulls by phosphoric acid and microwave activation were studied. Factors investigated in this study were temperature of carbonization at 300, 350, 400 and 450 ^๐C, and time of carbonization at 30, 60 and 90 minutes. The optimum yield was observed that carbonization temperature of 400 ^๐C and time at 60 minutes, respectively. The yield of charcoal was 39% and the fix carbon was 69%. Then the charcoal was activated by phosphoric acid and microwave irradiation, respectively. The effect of the weight per volume ratios of charcoal to activating acid (1:1, 1:2 and 2:1(W/V)), microwave power at (activated 300, 500 and 700 watts), and activated time (30, 60 and 90 seconds) were studied. The results showed that the optimum conditions for activating peanut charcoal were 1:2 (W/V) charcoal per activating acid, microwave power 700 watts for 90 seconds. The results yielding maximum surface area by BET method was 303.1 m²/g and pore volume was 0.140 cm³/g. An efficiency of maximum iodine adsorption was 418 mg iodine/g activated carbon. Comparing the adsorption eff iciency of non- irradiated and irradiated activated carbon, the efficiency of irradiated activated carbon improved up to 31%, due to its larger surface area and pore volume.