Yoshinori Kanjo*, Atsuko Kimoto** and Atsuhiro Honda***

*Osaka City University, Facl. of Engineering, Dept. of Civil Engineering, Research Associate
**Nihon Suido Consultant Co. Ltd.
***Clean Japan Center

+ Correspondence should be addressed to Kanjo Yoshinori
(3-3-138 Sugimoto, Sumiyoshi-ku, Osaka 558 Jpan)

Abstract

Preservative-treated wood with chromated copper arsenate (CCA) has been used for 50 years in the world because of its reliability in preventing damage by insects or microorganisms. However, if this treated wood is waste and is incinerated, it will cause serious problems, in that incineration gas is discharged with high concentration of arsenic compounds, and the ash residue contains a lot of copper, chrome, and arsenic compounds. In this paper, a series of extraction experiments was carried out to remove these hazardous materials from preservative-treated wood. Through the experiments, suitable conditions were obtained as follows; 1) suitable extractant is 0.25N sulfuric acid. 2) suitable temperature ranges between 90 *C[Celsius degeree] and 100 *C[Celsius degeree]. Moreover, the relationships between extraction time, extracted amount of TOC, and wood tip size were obtained.

Key words: preservative-treated wood, extraction treatment, extraction ratio, extracted amount of TOC