Basic density and pulp yield relationship with some chemical parameters in eucalyptus trees

Abstract

-The objective of this work was to evaluate the use of basic density and pulp yield correlations with some chemical parameters, in order to differentiate an homogeneous eucalyptus tree population, in terms of its potential for pulp production or some other technological applications. Basic density and kraft pulp yield were determined for 120 Eucalyptus globulus trees, and the values were plotted as frequency distributions. Homogenized samples from the first and fourth density quartiles and first and fourth yield quartiles were submitted to total phenols, total sugars and methoxyl group analysis. Syringyl/guaiacyl (S/G) and syringaldehyde/vanillin (S/V) ratios were determined on the kraft lignins from wood of the same quartiles. The results show the similarity between samples from high density and low yield quartiles, both with lower S/G (3.88-4.12) and S/V (3.99-4.09) ratios and higher total phenols (13.3-14.3 g gallic acid kg -1 ). Woods from the high yield quartile are statistically distinguished from all the others because of their higher S/G (5.15) and S/V (4.98) ratios and lower total phenols (8.7 g gallic acid kg -1 ). Methoxyl group and total sugars parameters are more adequate to distinguish wood samples with lower density.Index terms: Eucalyptus globulus, syringyl, guaiacyl, phenols, methoxyl group, kraft pulping. Densidade e rendimento em polpa celulósica e sua relação com alguns parâmetros químicos no eucaliptoResumo -O objetivo deste trabalho foi avaliar a aplicabilidade de correlações entre rendimento em polpa e densidade básica com alguns parâmetros químicos, para diferenciar uma população homogênea de árvores de eucalipto, em termos de capacidade de produção de polpa celulósica ou de outras aplicações. Determinou-se a densidade básica e o rendimento em polpa celulósica em 120 árvores de Eucalyptus globulus, e os resultados foram representados como distribuição de freqüências. Na madeira das árvores dos primeiro e quarto quartis de densidade e de rendimento, determinaram-se os teores de fenóis totais, açúcares totais e grupos metoxílicos. Nas respectivas ligninas kraft determinaram-se as razões seringilo/guaiacilo (S/G) e seringaldeído/vanilina (S/V). As amostras dos quartis de alta densidade e as de baixo rendimento foram semelhantes, ambas com baixos valores de S/V (3,99-4,09) e S/G (3,88-4,12) e os mais elevados teores de fenóis totais (13,3-14,3 g de ácido gálico por quilograma). As madeiras do quarto quartil de rendimento são estatisticamente distintas das outras, com as maiores razões S/G (5,15) e S/V (4,98) e os menores teores de fenóis totais (8,7 g de ácido gálico por quilograma). Os parâmetros grupos metoxílicos e açúcares totais são os mais adequados para a diferenciação das amostras provenientes do primeiro quartil de densidade.

Genetic Variation in the Chemical Components ofEucalyptus globulusWood

“…Our results suggest that the only correlated response expected from selection for increased wood density within E. globulus subraces is a tendency for lignin and S/G to decrease. A negative phenotypic correlation between S/G and wood density was found in E. globulus by da Seca and Domingues (2006) , a result that occurred at the phenotypic, additive genetic, and subrace levels in the present study. No additive genetic relationship was observed between density and extractives, similar to previous studies that also did not find a genetic ( Miranda and Pereira 2002 ; Poke et al 2006 ) or phenotypic ( Ona et al 1998 ) correlation.…”

Energy Product Options for Eucalyptus Species Grown as Short Rotation Woody Crops

“…Small variations of pulp yield and basic density can be predicted from some chemical parameters [ 37 ]. Woods with higher pulp yield had very distinctive syringyl/guaiacyl (S/G), syringaldehyde/vanillin (S/V), and total phenols, independent of basic density.…”

WOOD EVALUATION OF Eucalyptus pellita F.Muell. AND Eucalyptus tereticornis Smith AS POTENTIAL FOR PULP AND PAPER PRODUCTION

“…Wood density and pulp yield have been considered fundamental parameters in tree selection programs for pulping, in addition to tree growth (Silva et al, 2009;Borralho et al, 1993), and density is also a determining factor for the type of paper to be produced. Although, many studies have been showing that the density is vital for quality of pulp production (Scanavaca and Garcia, 2004;Trugilho et al, 2005;Santos et al, 2008b;Horáček et al, 2017), many others have been reported no correlation or weak correlation between these two properties (Miranda and Pereira, 2001;Seca and Domingues, 2006;Mokfienski et al, 2008;Silva et al, 2009). In this context, we highlight that the two species we studied have high wood density, E. pellita (0.939 g.cm -3 ) and E. tereticornis (0.800 g.cm -3 ), and a significant difference can be observed between them.…”