Some process aspects on acid sulphite pulping of softwood
(English)Manuscript (preprint) (Other academic)
Acid sulphite pulping is currently used for production of either paper grade pulp or dissolving grade pulp but its benefits are best seen when producing dissolving grade pulp. In this study acid sulphite pulping of either 100% pine or 100% spruce were carried out to investigate the effects of the cooking conditions on the final pulp composition. Higher cooking temperature had an impact on the delignification rate but also on the lignin condensation reactions. Lignin condensation reactions were found to have a strong negative influence on the yield of cellulose and hemicellulose compounds in the final pulp samples. The influence of time, residual content of cooking acid and temperature on the delignification rate and on the lignin condensation reactions were analyzed and it was found that lignin condensation reactions were very frequent if the cooking acid concentration was too low.
Acid sulphite; cellulose; extractives; hemicelluloses; lignin condensation.
Engineering and Technology
Research subject Chemical Engineering
IdentifiersURN: urn:nbn:se:kau:diva-46908OAI: oai:DiVA.org:kau-46908DiVA: diva2:1038870
FunderMoRe ResearchDomsjö FabrikerKnowledge FoundationThe Kempe Foundations