Eucalyptus globulus bark valorization: Production of fibers by Neutral Sulphite Semi-Chemical Process for Liner Paper Manufacture

Abstract Eucalyptus globulus is the second most important economic forest species in Chile. Its main use is in the kraft pulp industry, where large amounts of bark waste are generated. Due to its fibrous characteristics, E. globulus bark is proposed as an alternative source of fibres for papermaking. This study focuses on obtaining fibres for liner paper manufacture. A neutral sulphite semi-chemical (NSSC) process was performed, varying the sodium sulphite (5% to 16%) and the sodium carbonate (2% and 4%) concentrations using two reaction temperatures (160°C and 170°C). The NSSC process at 170°C, 16% of sulphite, and 2% of sodium carbonate proved to be the best condition to obtain higher mechanical performance of papers. As the pulping conditions become more drastic, the yield drops, and the physicomechanical properties of paper increases. Results showed that pulps from E. globulus bark could turn into source of fibres for papermaking and other related products.