OGAWA Hiroyasu Toho Rayon Co.Ltd., General Manager, 経営企画室, 部長(研究職)
IDE Isamu Lignyte Co.Ltd., , General Manager, 機能材料開発部, 取締役部長
KAWAUCHI Masataka Shin Maywa Ind., Co.Ltd., General Manager, 開発技術本部, 本部長
HATA Toshimitsu Kyoto Univ.Wood Res.Inst., Instructor, 木質科学研究所, 助手 (10243099)
IMAMURA Yuji Kyoto Univ.Wood Res.Inst., Assoc.Prof., 木質科学研究所, 助教授 (70151686)
吉田 貴司 (株)豊田自動機械製作所, 技術開発研究所, 主任
|Budget Amount *help
¥11,900,000 (Direct Cost: ¥11,900,000)
Fiscal Year 1997: ¥1,300,000 (Direct Cost: ¥1,300,000)
Fiscal Year 1996: ¥10,600,000 (Direct Cost: ¥10,600,000)
Many research on the utilization of tree plantation thinnings, lesser used species and other wood wastes have been conducted but the ideal solutions have yet to be found. In cooperation with other researchers, in order to develop new composite materials from transtition metal oxides and charcoal from wood wastes for removal of NOx or its conversion into harmless gases, three new carbonization systems for the mass production of wood charcoal which are low-energy, non-pollutant and continuous process were developed. The products are of consistently high quality.
Wood powder carbonized at 1000 and 1400ﾟC,and activated charcoal had considerably larger specific surface areas compared to those carbonized at 200,600,1800 and 2200ﾟC.No large difference was observed on the pore size distribution and specific surface areas between wood powder and wood carbonized at 200,600,1800 and 2200ﾟC.Wood powder carbonized at 1000 and 1400ﾟC as well as activated charcoal created more micropores with radii be
low 10 nm. The formation and disappearance of micropores might have an effect on the similar tendency between pore size distribution and specific surface area.
When the carbonization temperature was 600ﾟC,the concentration of NO was the lowest in all the samples of Nox after passing NO through wood charcoals and activated charcoal, that is, the wood powder carbonized at 600ﾟC indicated the best conversion or adsorption ability, even though the specific surface area and pore size distribution of wood powder carbonized at 600ﾟC were not remarkably large compared to wood carbonized at 1000ﾟC and acivated charcoal. It seems that the conversion of the adsorption ability has nothing to do with physical properties. On the other hand, the concentration of NO_2 was not detected among every sample. It is clear that every charcoal except wood powder has good NO_2 conversion or adsorption ability. Very little concentration of NO was detected from every carcoal. It was observed that wood charcoal reduced NO_2 to NO.
When metal oxide-dispersed wood charcoal was ovendried at 105ﾟC, the NO conversion and the reduction efficiency from NO_2 to NO decreased compared to wood charcoal. However, the capacity to convert or adsorb NO was improved by heat treatment of the composite at 600ﾟC.Particularly, vanadiumoxide-dispersed wood charcoal showed the highest tendency to convert or adosorb greater amount of NO.When metal oxide-dispersed wood charcoals were illuminated by monochromatic light with near wavelength of ultraviolet rays, titanium oxide-despersed wood charcoal remarkably decreased the concentration of NO.The shorter the wavelength became, that is, as the light energy increased, the better the conversion or adsorption ability. From this result, it was found that oxide of transiton metal performed as photocatalyst since based from the result, vavadium or titanium oxide oxidizes or reduces NO by light energy.
Removal of NO or its conversion into NO or N_2 by the zeolite-dispersed wood charcoal were decreased with an increase in content of zeolite on the wood charcoal. Less