Effect of different saturation methods on mass loss and color of Eucalyptus spp. wood chips
Name: SAULO JOSÉ DA COSTA LIMA
Publication date: 27/02/2025
Examining board:
Name |
Role |
|---|---|
| DALTON LONGUE JÚNIOR | Examinador Externo |
| DJEISON CESAR BATISTA | Presidente |
| THAYANNE CAROLINE CASTOR NETO | Examinador Externo |
Summary: The aim of this study was to evaluate the effect of three different saturation methods on the mass loss and color of Eucalyptus spp. wood chips. We tested chips from clones of three species (E. grandis, E. urophylla and E. grandis × urophylla) with pre-established levels of basic density (“low”, “medium” and “high”). The Control saturation method (M1) consisted of that proposed by the standard NBR 11941 (application of only vacuum during the saturation process), and the others (M2 and M3) were adaptations of the standard, in which pressure and temperature (70 °C and 100 °C) were applied, in addition to vacuum. The analyses of the chips included mass loss, colorimetry (CIELab color space), solubility in cold water, and two ways of calculating basic density (methods of the hydrostatic balance – MBH and the maximum moisture content - MMTU). Except for E. grandis, the saturation methods caused significant mass losses in the chips, with percentages of up to 2.37%, especially for M3. The chips darkened and the color change caused by saturation was classified as “large” and “very large”, evidencing significant changes in the tone of the wood. However, the saturation methods did not interfere in the determination of the basic density of the chips, regardless of the calculation method used (MBH and MMTU); that is, the mass/volume ratio of the wood was not modified by the mass loss, and the density calculation methods did not differ from each other. In addition, the time required for chip saturation was reduced by up to five days (M3).
Keywords: Mass loss; CIE Lab; basic density; water solubility; hydrostatic balance method; maximum moisture content method.
