Polysulphide pretreatment of softwood for increased delignification and higher pulp viscosity
2004 (English)In: Journal of Pulp and Paper Science (JPPS), ISSN 0826-6220, Vol. 30, no 5, 129-135 p.Article in journal (Refereed) Published
The effect of polysulphide pretreatment under various conditions prior to a kraft cook was investigated for spruce (Picea abies) chips using a technique with a liquor:wood ratio of 67:1 to keep the liquor composition as constant as possible during the pretreatment and cooking phases. If the polysulphidepretreatment is carried out at a very high hydroxide concentration, 1.5 mol OH-/L, three independent positive effects (compared with a corresponding sulphide pretreatment without polysulphide) can be observed: more extensive delignification; higher pulp, viscosity; and higher carbohydrate yield. When the alkali change was changed in the subsequent kraft cook (in the range 0.15-0.60 mol/L), the increase in delignification extent as a result of polysulphide pretreatment was not affected but the relative carbohydrate yield increase was favoured by a higher alkali charge during cooking. On the other hand, the absolute carbohydrate yield is favoured by a intermediate alkali charge.
Place, publisher, year, edition, pages
2004. Vol. 30, no 5, 129-135 p.
pretreatment, chips, picea abies, kraft pulping, polysulfides, liquor ratio, hydroxides, concentration, alkali consumption, delignification, viscosity, carbohydrates, yield
Other Chemistry Topics
IdentifiersURN: urn:nbn:se:kth:diva-23530ISI: 000222250700003ScopusID: 2-s2.0-2442530323OAI: oai:DiVA.org:kth-23530DiVA: diva2:342228
QC 201005252010-08-102010-08-102011-11-02Bibliographically approved