Fluid Flow in Nanosilver-Impregnated Heat-Treated Beech Wood in Different Mediums

Abstract

Specific gas permeability of beech wood was determined and compared with values obtained after nanosilver-impregnation and heat-treatment in three mediums of air, water, and water steam at 150 °C for four durations of 1, 2, 3, and 4 h. Separate sets of specimens for each group were prepared and impregnated with a 400 ppm aqueous nanosilver suspension. The results revealed that the effect of heat treatment in hot-air depended on the duration of treatment. Hydrothermal treatment generally increased gas permeability, this was attributed to the dissolving of extractives in the hot water medium, although lower duration of one hour did not significantly change permeability. Hygrothermal treatment increased gas permeability at all four durations, revealing its effectiveness as a pre-treatment to improve penetration of preservatives and fire-retardants into wood texture in wood preservation industry. High thermal conductivity of silver nanoparticles intensified the effects of heat treatment in all mediums.

Changes of Meranti, Padauk, and Merbau Wood Lignin during the ThermoWood Process

“…Given the similarity of the trends of the measured absorbances for meranti, padauk, and merbau, the FTIR spectra will be evaluated together (in the case of more significant unequal behavior between them, this will be mentioned). A broad band around 3400 cm −1 (OH stretching vibration in alcohols, acids, phenols, and weakly bounded absorbed water in lignin) [ 22 , 48 ] and bands around 2940 and 2840 cm −1 (C−H stretching in methyl and methylene groups) [ 49 , 50 ] show only negligible changes in absorbance during the thermal treatment. The absorbance of the band at 1710 cm −1 (C=O vibrations of non-conjugated carbonyl groups) increases with the increasing temperature (with a maximum at 210 °C).…”

The Impact of Thermal Treatment on Structural Changes of Teak and Iroko Wood Lignins

“…Its main objective is to improve dimensional stability and durability, but sometimes thermal treatment is used to change the aesthetic properties of wood. The wood colour becomes darker depending on the treatment temperature, time, and environment [2][3][4].…”

Advances in Wood Composites II

“…An alternative means, probably more attractive, is so-called nanotechnology. Nanomaterials have unique characteristics, penetrate effectively and deeply into the wood substrate and improve fundamental properties [18][19][20][21][22][23][24][25][26][27][28][29][30][31].…”