A comparative study of the impact of the cooking process on oxygen delignification
2003 (English)In: Nordic Pulp & Paper Research Journal, ISSN 0283-2631, Vol. 18, no 4, 388-394 p.Article in journal (Refereed) Published
The impact of oxygen delignification on chemical pulps of a given kappa number manufactured in different ways (using kraft, prehydrolysis kraft and magnesium sulphite cooking) has been investigated. The prehistory of the pulps proves to be a very important factor in determining the response to oxygen delignification, i.e. the degree of delignification. It is shown that this is not due to different amounts of hexenuronic acid (HexA) in the different pulps, although this is an important factor behind the high residual kappa number after oxygen delignification of birch kraft pulp. Oxygen delignification of sulphite pulps proves to be efficient even at kappa numbers significantly lower than 10. These pulps show the greatest yield loss over the oxygen delignification. It is likely that Lignin Carbohydrate Complexes (LCC) complexes play a very important role in limiting the speed of reaction of oxygen delignification. Due to the very different prehistories of the pulps investigated, it is probable that the LCC:s are native and not formed during cooking.
Place, publisher, year, edition, pages
2003. Vol. 18, no 4, 388-394 p.
oxygen delignification, kraft cooking, prehydrolysis kraft cooking, magnesium sulphite cooking, spruce, birch, final pH, kappa number, kappa number, part ii, lignin, pulps
IdentifiersURN: urn:nbn:se:kth:diva-23157ISI: 000188873000005OAI: oai:DiVA.org:kth-23157DiVA: diva2:341855
QC 201005252010-08-102010-08-10Bibliographically approved