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- Some preliminary data on the enzymatic hydrolysis of Pinus pinaster kraft pulpPublication . Duarte, Ana Paula; Spiridon, IulianaEnzymes' applications in pulp and paper manufacturing processes and products is gaining global attention. In fact, several applications, including pitch deposits, drainage enhancement, deinking of wastepapers, pulp bleaching enhancement and modification of fibers' characteristics are already used at industrial level. Enzymes are being produced on a commercial scale and are available at a relatively low price. Research to establish the effect of enzymatic treatment continues in an effort to increase knowledge about the action of enzymes. The present paper, an additional contribution to this field, studies the potential utilization of hydrolytic enzymes to enhance the fiber characteristics derived from Pinus pinaster kraft pulp.
- Influence of xilanase treatment on Pinus pinaster kraft pulpPublication . Spiridon, Iuliana; Duarte, Ana Paula; Curto, JoanaIn Portugal, pulp and paper industry uses especially two wood species, Eucalyptus globules and Pinus pinaster. The second species gives pulps with low bleachability (compared with other common softwood species, like Pinus silvester), utilised for packaging papers. It is known that treatments with different hydrolytic enzymes could improve the bleaching capacity of softwood pulp. That is why, xylanases were used to improve Pinus pinaster kraft pulp characteristics. The enzymatic hydrolysis improved brightness and some papermaking properties.
- Behaviour of two main portuguese wood species towards enzymatic hydrolysisPublication . Spiridon, Iuliana; Belgacem, Mohamed Naceur; Duarte, Ana PaulaThis paper presents the influence of cellulolytic and hemicellulolytic enzymes on the papermaking properties of pulps from Eucalyptus globulus and Pinus pinaster wood species from Portugal. It was shown that these enzymes increased the delignification efficiency and degraded the cellulose macromolecules, having effects on the fiber strength. Thus, it was found that these treatments decreased strongly the burst index, but increased significantly the tearing properties. The zero span tensile strength was also affected, especially for Eucalyptus globulus pulps. Finally, these treatments were found to increase the brightness of the treated pulps.
- Enzymatic hydrolysis of Pinus pinaster kraft pulpPublication . Duarte, Ana Paula; Spiridon, Iuliana; Belgacem, Mohamed Naceurkraft pulp from Pinus pinaster was treated with two enzymes preparations - Cartazyme MCX-A (which presents both cellulase and xylanase activity) and Cartazyme PS-10 (a xylanase preparation) to enhance papermaking properties of the fibres. Both preparations reduced Kappa number and improved brightness, while the effect on the papermaking properties was different.