The Activated Carbon from Walnut Shell Using CO2 and Methylene Blue Removal

Abstract

In this study, activated carbon with strong adsorption property was synthesized from lignocellulosic structured walnut shell. Active carbon synthesis was realized in two stages: carbonization and physical activation. Carbonization was carried out at eight different temperatures (300-1000°C), 500 mL/min N2 gas flow and 10°C/min heating rate for 1 hour. Activation was done at two different temperatures (800- 900 °C) at 100 ml/min CO2 gas flow for 1 hour. Characterization of activated carbons was carried out and their adsorption capacities were examined with methylene blue. The surface areas of the activated carbons were investigated by BET analysis and the surface areas ranged from 56,79 to 652,22 m2/g. Amounts of micro and mesoporous in these surface areas were calculated. Besides, SEM analysis indicates the porous structure and XRD analysis confirms that the structure is amorphous. Methylene blue adsorption was performed in the aqueous phase and the capacities of the activated carbons were calculated. The methylene blue adsorption capacity of activated carbons varies between 15,96 -174,81 mg/g.