Abstract: By means of scanning electronic microscopy(SEM), automated specific surface-area and pore-size analysis, microporous structure of charcoal from Chinese fir wood carbonized under different temperatures was studied. With emphasis on formation of micropore and variation pattern, pore-size distribution, specific surface area and characteristics of pores were observed and analyzed. Results showed that both specific surface area and specific pore volume of charcoal increased with increased carbonization temperature.Carbonized material from higher temperature possessed more developed structure and larger specific surface area.Under high temperature, microporous structure was improved by burning off orderless carbon. By means of SEM, observation on state of microstructure of carbonized material showed that with increased carbonization temperature,amount of surface sediment on tracheid wall of carbonized material reduced and its particlesize became smaller,the layers of pits were gradually destroyed, and pit pores were opened. Observation on state of electric discharge under SEM showed that conductivity of carbonized material was increased with increase of carbonization temperature.

Key words: microporous structure, wood charcoal, thinning wood of Chinese fir