抄録
Bamboo charcoals were prepared by low temperature carbonization at 500 °C, and subsequent treatments such as air oxidation at 180-380 °C for the introduction of functional groups on the surface, and outgassing at 1000 °C for their removal were conducted to examine the relationship between the amount of water vapor adsorption and the surface properties of the prepared charcoals. The air oxidation treatment was effective in developing surface area and pore volume as well as surface functional groups, and the developments were in proportion to the treatment temperature. Air oxidation of the prepared charcoal at 380 °C increased surface area from 250 m2/g to 590 m2/g and pore volume from 0.16 mL/g to 0.31 mL/g. At a relative humidity below 50%, the charcoals oxidized at 380 °C were able to adsorb approximately twice the amount of water vapor compared to those oxidized at 180°C and 280 °C, indicating that the water vapor adsorption depends on the surface functional groups. In a relative humidity above 50%, the outgassed bamboo charcoals adsorbed a large amount of water vapor, indicating that mesopores and macropores, rather than surface functional groups, contributed to water vapor adsorption.
