Production of activated carbon by K₂CO₃ activation treatment of cornstalk lignin and its performance in removing phenol and subsequent bioregeneration

Activated carbon was produced by fast precarbonization of cornstalk lignin in a fluidized bed followed by K₂CO₃ activation. The results showed that the product is essentially microporous carbon whose Brunauer-Emmett-Teller surface area and pore volume when the carbon was activated at 800°C were 1410 m²/g and 0.77 mL/g, respectively. The potential usefulness of the resultant carbons for removal of phenol from water and their subsequent bioregeneration capabilities were also investigated. The kinetics study showed that all the carbons exhibited a fast adsorption rate and the carbon activated at 800°C had the largest amount of phenol adsorbed due to its greater specific surface area and pore volume. The adsorption isotherms by applying the Langmuir method showed that the monolayer adsorption capacity of carbon activated at 800°C could reach 110.9 mg/g.