Efforts to recover CCA from CCA-treated wood have been focused on the extraction of small wood particles. This work describes a method capable of removing CCA from retired CCA treated pine boards without. The percent removal of copper varied from 82% to 94%, 72% to 90% for chromium, and 84% to 98% for arsenic. The mechanical properties of boards after the extraction of CCA was reduced to 30% compared to un-extracted CCA treated boards. The extraction solution containing CCA was concentrated and the chromium 3 oxidized to chromium 6. The resulting CCA solution was used to treat southern pine cubes at a target retention of 6.4 kg/m3. After a laboratory soil block test, the indices of protection of cubes treated with the recovered CCA was comparable to that of cubes treated with fleshly obtained CCA and the weight loss of cubes after the CCA removal was similar to untreated pine sapwood control.

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