Performance of Carbonized Sugi Wood and Bark for Humidity Control
2002 年 51 巻 3Appendix 号 p. 38-42
詳細
2002 年 51 巻 3Appendix 号 p. 38-42
Sugi (Japanese cedar, Cryptomeria japonica D. Don) wood or bark were heated at 500-900°C for 3h to investigate the effect of treatment temperature on the surface properties and the humidity control capacity of carbonized materials. The specific surface area of micropore (pore radius=0.64-1.0nm) and mesopore (>1.0nm) were estimated by the adsorption isotherm of nitrogen gas at 77K. The humidity control tests were carried out in a sealed batch system at a temperature range of 15-25°C for 3-24h cycles. The initial relative humidity (RH) at 20°C was 65%. The micropore surface area of the carbonized woods varied depending on the treatment temperature. These increased significantly from 0m2/g to 441m2/g when the temperature increased from 500°C to 900°C. In contrast, the mesopore surface area was almost constant regardless of the treatment temperature, being 39-79m2/g. The maximum performance of humidity control was obtained with the wood or bark carbonized at 600°C in 3h and 6h cycles. The change in RH for 24h cycle at the sample of 3.0mg/cm3 was kept within a range of 3%. In addition, the ability for 3 to 24 hour-cycle humidity control was equivalent to that of 1 to 3/5 of a commercial silica gel used in museums. Carbonized wood and bark prepared at any temperature did not differ from un-carbonized wood in the humidity control capacity at 24h cycle.
