Arundo donax cane as a precursor for activated carbons preparation by phosphoric acid activation

T. VERNERSSON; P. R. BONELLI; E. G. CERRELLA; A. L. CUKIERMAN

BIORESOURCE TECHNOLOGY

ELSEVIER SCIENCE LTD.

Lugar: OXFORD, UK; Año: 2002 vol. 83 p. 95 - 104

0960-8524

Canes from Arundo donax, a herbaceous rapid-growing plant, were used as precursor for activated carbon preparation by phosphoric acid activation under a self-generated atmosphere. The in.uence of the carbonization temperature in the range 400?550 °C and of the weight ratio phosphoric acid to precursor R= 1:5?2:5Þ on the developed porous structure of the resulting carbons was studied for 1 h of carbonization time. Surface properties of the activated carbons were dependent on a combined e.ect of the conditions employed. Carbons developed either with R = 1:5 over the range 400?500 °C, or with R =2 at 500 °C exhibited surface areas of around 1100 m2=g, the latter conditions promoting a larger pore volume and enhanced mesoporous character. For both ratios, temperature above 500 °C led to reduction in porosity development. A similar e.ect was found for the highest ratio R = 2:5 and 500 °C. The in.uence of carrying out the carbonization either for times shorter than 1 h or under .owing N2 was also examined at selected conditions (R = 2, 500 °C). Shorter times induced increase in the surface area ( 1300 m2/g), yielding carbons with smaller mean pore radius. Activated carbons obtained under .owing N2 possessed predominant microporous structures and larger ash contents than the samples derived in the self-generated atmosphere.