Evaluation of the correlations between copper stabilization and valence conversion on copper leaching from ACQ-D treated wood

Red pine (Pinus resinosa Ait.) wood cubes (19.0•19.0•19.0 mm) were treated with amine copper quat (ACQ-D) solution and fixed in different post-treatment conditions. The correlations between copper leaching, copper conversion and copper stabilization were analyzed. The results showed that higher temperature and relative humidity are positive conditions for copper fixation. The copper leaching resistance of ACQ-D treated red pine post-treated at 50°C for more than 24 h is similar to that post-treated at 120°C only for 2 h. During different post-treatments, a higher copper conversion rate usually corresponds to a lower copper leaching, the same trend also can be found in the relationship between copper fixation and copper leaching, which demonstrates post-treatment conditions bring about higher copper conversion and copper stabilization during copper fixation process are positive measurements for improving copper leaching resistance of ACQ-D treated wood.