Copper-ethanolamine solutions are the most important wood preservatives in use class 3 and 4 applications. Fixation of these preservatives is finished within 2 to 24 hours. However, the efficacy of fixation decreases within time. Therefore, influence of the various conditioning methods (anoxic conditions, dry climate, wet climate, etc.) on copper leaching was elucidated. Spruce wood specimens were impregnated with Silvanolin aqueous solution of 3 different concentrations (cCu = 0.1 %, 0.25 % and 0.5 %). After impregnation, specimens were conditioned for 10 days in various regimes and afterwards leached according EN 1250 protocol. The results clearly showed that lower Cu emissions were determined from the specimens impregnated with aqueous solutions of higher concentrations. The highest Cu leaching (2.8 %) was determined at specimens impregnated with Cu solution of middle concentration (cCu = 0.25 %) and dried at 50 °C. On the contrary, at specimens impregnated with solution of the highest concentration and dried at 25 °C the lowest Cu emissions were determined (1 %). In general, Cu fixation at specimens conditioned at higher relative air humidity was better compared to the specimens dried in dry climate. Additionally, drying in anoxic conditions have positive effect on Cu fixation.
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