Bleached NSSC pulps from eucalyptus species

AREA, M.C.; FELISSIA, F.E.; CLERMONT J.E.; NÚÑEZ C.E.; VENICA, A.D.

CELLULOSE CHEMISTRY AND TECHNOLOGY

Romanian Academy, Publishing House of the Romanian Academy

Año: 2007 vol. 41 p. 195 - 202

0576-9787

The work discusses comparatively the chemical and microscopical characteristics of Eucalyptus globulus, E. grandis, E. viminalis, E. dunii, and E. cinerea, and neutral sulphite semichemical pulping of the first four species. The wood properties were correlated with NSSC (Neutral Sulphite Semichemical) pulp properties. Results indicate that the pulp obtained from E. grandis is characterized by the highest energy consumption and superior properties, while the pulp from E. globulus requires the lowest quantity of refining energy, but its properties are, in general, inferior. Pulps from E. dunii and E. viminalis behaviour can be considered as possessing intermediate properties. Statistical correlations indicated that the hemicelluloses present in wood favourized refining, yet produced low tensile and burst strength. The lignin content increases the refining energy consumption and tensile strength. While the highest length / width relationship in fibres favourizes the pulp properties, fibre flexibility (or collapse capacity) shows the contrary effect. Pulps from E. globulus and E. viminalis present similar bleachability and good final brightness.