The effect of steam conditioning on Southern yellow pine treated with copper naphthenate
Jun Zhang, D P Kamdem, M H Freeman, R D Arsenault
The current study was undertaken to investigate the influence of steam conditioning on Southern yellow pine treated with copper naphthenate (Cu-N). Pre-steamed and /or kiln-dried Southern yellow pine were pressure treated with Cu-N. After treatment, one group of samples were post-steamed. It was found that samples changed color from green to dark-brown after post-steaming. To elucidate the effect of steaming on treated wood, several techniques, namely, environmental scanning electron microscopy equipped with energy dispersive X-rays analysis (ESEM-EDXA), X-ray diffractometry (XRD), and X-ray photoelectron spectroscopy (XPS) were employed. After post-steaming, ESEM showed clearly crystal deposit on the Cu-N treated samples, and EDXA data suggested that the crystal was copper and oxygen contained compound identified as Cuprous Oxide (Cu2O) by XRD. The amount of Cu2O in wood samples was semi-quantitatively determined with XRD. XPS C1s spectra showed that post-steaming decreased C1 contribution and increased O/C ratio attributed to the loss of oil rich in hydrocarbons. The removal of water solubles extractives rich in carbon explains the decrease of O/C ratio. The resistance of copper to water leaching was improved by pre-steaming contrary to the post steaming which resulted in high copper loss.
Keywords: XPS; XRD; ESEM-EDAX; COPPER NAPHTHENATE; STEAM; SOUTHERN YELLOW PINE
Conference: 97-05-25/30 Whistler, British Columbia, Canada