Production of activated carbon by H₃PO₄ activation treatment of corncob and its performance in removing nitrobenzene from water

Activated carbon was produced by fast precarbonization of corncobs in a fluidized bed followed by H₃PO₄ activation. The results showed that the product is essentially microporous carbon whose BET surface area and pore volume when the carbon was activated at 900°C were 1588 m ²/g and 0.8163 mL/g, respectively. The experimental operating conditions were as follows: carbonizing the corncobs in the preheated fluidized-bed at 350°C for 5 min using N₂ as carrier gas; impregnating the char with H₃PO₄ with an impregnation ratio of 1:5 (Char/H₃PO₄); and activating the mixture at 900°C for 30 min in the tubular furnace. The potential usefulness of the resultant carbons for removal of nitrobenzene from water was also investigated.