Abstract
Abstract Japanese cedar (Cryptomeria japonica D. Don) bark was pyrolyzed in a stream of N2 at 473-673K for 3-12h under atmospheric pressure. The resultant carbonaceous residues were activated in a stream of CO2 at 1173K for 1h. Adsorption of N2 at 77K was measured to investigate the pore structure and the surface properties of the pyrolyzed and activated materials from the cedar bark. Both specific surface areas and total pore volumes of the materials pyrolyzed at temperatures below 573K were small, indicating that pore structures were not developed under mild conditions. However, those of the samples heated at 673K increased with increasing time of the treatment, during which micro porosity was mainly developed. Activation of the pyrolyzed cedar bark led to drastic increase in specific surface area and pore volume. The increase was due to the selective formation of the micro pores which distributed mainly less than 0.35nm in radius. Analytical results of adsorption data using t-plot and αs-plot and IR spectra methods suggest that the surface properties of both pyrolyzed and activated cedar bark are different from those of typical carbon black. It is indicated that organic moiety and oxygenated functional groups originated from cedar bark may affect the surface characteristics of pyrolyzed and activated cedar bark.
