Effect of microwave-assisted impregnation on the leaching resistance of ACQ in refractory spruce wood

Microwave (MW) treatment is an environmentally friendly and time-saving technique with great potential for generating wood-impregnation innovations. In this study, a microwave-assisted impregnation (MWAI) approach was developed to achieve adequate retention and fixing of alkaline copper quaternary (ACQ) in refractory spruce wood. The synergistic effect of MW pre- and post-treatments in the impregnation procedure on wood’s compressive strength (CS) and copper leaching resistance and valence conversion was investigated. In conclusion, high-intensity MW pre-treatment and low-intensity MW post-treatment provided optimum results for the fixation of copper. Based on the results of the copper conversion assays, the same MWAI procedure is also predicted to give high biological efficiency.