A method for detoxifying spent CCA (copper, chromium, arsenic) treated wood, from which CCA is efficiently removed from the wood, allowing both the CCA and the wood to be reused has been developed. The method comprises the steps of (1) microwave-enhanced acid extraction of CCA, (2) separation of the acid-containing CCA solution from the wood, (3) separation/precipitation of CCA from the acid extract, (4) recovery and regeneration of CCA-bearing precipitant for reuse in the wood preservation industry, (5) recycling recovered acid solution, (6) microwave-assisted liquefaction of the extracted wood, and (7) use of detoxified liquefied wood to form polymeric materials such as polyurethanes and phenolic resin adhesives. The recovered CCA may be used to treat wood. The recovered acids may be used to extract CCA from CCA-treated wood, and the liquefied wood may be used as phenolic or polyurethane resins.