Delignification and bleaching response of earlywood and latewood
2006 (English)In: Journal of wood chemistry and technology, ISSN 0277-3813, E-ISSN 1532-2319, Vol. 26, no 4, 325-337 p.Article in journal (Refereed) Published
The delignification response in cooking and the impact of bleaching on earlywood and latewood were studied. Spruce earlywood and latewood chips were pulped by the kraft process and subsequently treated with one bleaching chemical at a time. In cooking, latewood required a higher alkali charge to reach the same kappa number. No difference in the light absorption coefficient between the different fiber types was observed. After oxygen delignification the earlywood fibers had a higher light absorption coefficient at the same kappa number. The difference in light absorbing material was maintained when bleaching was performed with chlorine dioxide, ozone, and peracetic acid. Hydrogen peroxide decreased the light absorbing structures in the earlywood to the same level as for latewood. The earlywood pulp had a higher brightness at a given kappa number than the latewood. The higher brightness remained through all bleaching operations and was primarily due to a higher light scattering ability.
Place, publisher, year, edition, pages
2006. Vol. 26, no 4, 325-337 p.
softwood, latewood, earlywood, delignification, bleaching response, loblolly-pine
IdentifiersURN: urn:nbn:se:kth:diva-16285DOI: 10.1080/02773810601076881ISI: 000242799400004ScopusID: 2-s2.0-33845506867OAI: oai:DiVA.org:kth-16285DiVA: diva2:334327
QC 201005252010-08-052010-08-052011-07-08Bibliographically approved