Química Nova | |
INFLUÊNCIA DO CONTEÚDO DE XILANAS NA BRANQUEABILIDADE, PROPRIEDADES HIGROSCÓPICAS, FISICO-MECÂNICAS E ÓPTICA DE POLPAS BRANQUEADAS DE EUCALIPTO | |
Valéria J. Gomes1  Dalton Longue Jr1  Jorge L. Colodette1  Robisnéa A. Ribeiro1  Heder Braun1  | |
关键词: xylans; alkaline extraction; bleachability; hygroscopic properties; optical properties; | |
DOI : 10.5935/0100-4042.20140309 | |
来源: SciELO | |
【 摘 要 】
Bleached eucalypt kraft pulps are widely used in print and writing (P&W) and tissue paper manufacture. Among the quality requirements of pulp for these papers, xylan content has been controversial. The objective of this study was to evaluate the influence of xylan content on bleachability, hygroscopic, physic-mechanical and optical properties of the pulp. In this study industrial unbleached eucalyptus kraft pulp (15.6% xylans) treated with different NaOH loads to change its xylan content was used. Subsequently, pulps were bleached by the ODHT(EP)D sequence to achieve 90% ISO of brightness, then refined and submitted to hygroscopic, physicomechanical and optical tests. NaOH treatments decreased the xylan content to 14.5-5.9% using NaOH loads of 10-70 g L-1. Pulp bleachability was not significantly affected by xylan content decrease. The decrease in xylan content negatively affected the water retention value and Klemm capillarity of the pulp, while water absorption capacity was positively affected. Tensile and tear index were negatively influenced by the reduction in xylan content, whereas bulk and light scattering coefficient increased.
【 授权许可】
CC BY-NC
All the contents of this journal, except where otherwise noted, is licensed under a Creative Commons Attribution License
【 预 览 】
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RO202103040064716ZK.pdf | 325KB | download |