Activated carbon from thermo-compressed wood and other lignocellulosic precursors

• Published in: Bioresources Vol. 2; no. 2; pp. 193 - 209
• Main Authors: Khezami, Lotfi, Ould-Dris, Aissa, Capart, Richard
• Format: Journal Article
• Language: English
• Published: North Carolina State University 01.05.2007
• Subjects: Activated carbon; Adsorption properties; Microporosity; Thermo-compression; Wood
• ISSN: 1930-2126; 1930-2126
• DOI: 10.15376/biores.2.2.193-209

The effects of thermo-compression on the physical properties such as bulk density, mass yield, surface area, and also adsorption capacity of activated carbon were studied. The activated carbon samples were prepared from thermo-compressed and virgin fir-wood by two methods, a physical activation with CO2 and a chemical activation with KOH. A preliminary thermo-compression method seems an easy way to confer to a tender wood a bulk density almost three times larger than its initial density. Thermo-compression increased yield regardless of the mode of activation. The physical activation caused structural alteration, which enhanced the enlargement of micropores and even their degradation, leading to the formation of mesopores. Chemical activation conferred to activated carbon a heterogeneous and exclusively microporous nature. Moreover, when coupled to chemical activation, thermo-compression resulted in a satisfactory yield (23%), a high surface area (>1700 m2.g-1), and a good adsorption capacity for two model pollutants in aqueous solution: methylene blue and phenol. Activated carbon prepared from thermo-compressed wood exhibited a higher adsorption capacity for both the pollutants than did a commercial activated carbon.