Chemical remediation of wood treated with micronised, nano or soluble copper preservatives

Abstract

The potential for extraction of copper from wood treated with micronised, nano or soluble forms of copper has been evaluated in view of chemical remediation. In focus were EDTA, oxalic acid, bioxalate, and D-gluconic acid for extraction of Cu from treated wood. Bioxalate extractions for 24 h resulted in Cu removal over 95% for all tested materials, and the effectiveness of oxalic acid extraction was very similar to that of nano-CuO-treated wood. Bioxalate was more effective than oxalic acid in removing Cu from ACQ-D, MCQ, MCA, CA-C and Cu-ethanolamine treated wood. D-gluconic acid extractions resulted in the lowest Cu removal for nano-CuO even though D-gluconic acid was effective for all other materials. As the pH of D-gluconic acid decreased, Cu removal was improved except for nano-CuO. There is no distinctive difference in Cu removal from wood treated with ACQ-D, MCQ, CA-C, MCA and Cu-ethanolamine.