Study on Leaching of Copper Nanoparticles in Combined Impregnation- Densification Treatments of wood after Accelerated Aging

This study was performed to evaluate the leaching rate of copper nanoparticles in combined impregnation-densification treated poplar and spruce wood after accelerated aging. Specimens were prepared by impregnation with 200 and 400 ppm nano-copper suspensions، followed by pre-steam treatment and densification. Impregnation was done in a sealed vessel with 4 bar pressure in 20 minutes. Half of the specimens were oven-dried and steamed at 150°C for 2 hours and immediately densified under the hot press at 170°C for 3 hours to reach to the 33% compression rate. All specimens were exposed to the 6 steps accelerated aging procedure according to ASTM D-1037. Leaching test was performed according to EN84 standard (1997) for a period of 14 days. The leached residues were investigated in the Mineral Exploration and Geological Center by atomic absorption method. Results showed that nano-copper particles in impregnated specimens had no leaching; but the pre-steaming and densification treatments led to leaching the nano-copper particles from the treated wood.