Effect of Sodium Xylenesulphonate Use in Bleached Kraft Pulp from Eucalyptus Wood on the Physical, Optical, and Mechanical Properties

Abstract

Sodium xylenesulphonate (SXS) was evaluated in wood chip pretreatment in order to improve the quality and the properties of bleached eucalypt kraft pulp. First, the chips were subjected to pretreatment with SXS, and then the pretreated chips were cooked by the kraft process. The resulting pulp was subjected to oxygen-delignification and then to bleaching. Various bleached pulp properties, such as fiber morphology, physical, optical and mechanical strength, were measured. The pulp from the SXS pretreated chips had higher lignin removal efficiency in oxygen delignification, which resulted in higher bleachability and lower bleach consumption compared with the reference pulp. The physical and optical properties of the pulp from the SXS pretreated chips had higher drainability, capillarity water absorption, specific volume, roughness, and opacity versus the reference pulp. These observations indicated that the pretreated pulp has the potential to be used in tissue pulp grades. However, the pulp obtained from the SXS pretreated chips had lower mechanical strength properties than the reference pulp. In sum, SXS chip pretreatment can be used to produce a pulp that has high bleachability and is suitable for tissue grades.