Abstract
It is important to recycle the old wood used in houses. Recently it is investigated to obtain charcoal from used wood. On the other hand, CCA treated wood is included in used wood. Because of including Arsenic, treated wood is not good for atmosphere in carbonization to obtain charcoal with high temperature. So we have tried to select out CCA treated wood from non-treated one. Surface of treated wood is a little bit greenish compared with non-treated one, so we first investigated the difference of the color phases. There are some differences for newly treated wood, but it is very difficult to find the method to select used CCA treated wood actually. We tried to detect CCA color from the surface of used wood using many kinds of chromaticity diagram.
