Leaching of copper from wood treated with copper-based wood preservatives

Copper-based preservatives are widely used for wood protection. Traditionally, copper salts were combined with chromium, as chromium fixes copper into wood and thus prevents leaching of these preservatives. Since carcinogenic nature of chromium compounds is well known, several European countries intend to ban or limit the use of chromium in wood preservatives. Therefore, our aim was to find proper substitutes for chromium. Amines seem very efficient in fixing copper into wood. Leaching of copper significantly depends on various factors such as copper source, amine ligand, molar ratio Cu:N and pH of treatment solutions. Copper carboxylates in aqueous solution of ethanolamine were found promising for further research and use.