Bleaching of softwood kraft pulps with H2O2, O3, and ClO2
1996 (English)In: TAPPI Journal, ISSN 0734-1415, Vol. 79, no 1, 113-119 p.Article in journal (Refereed) Published
Ozone or chlorine dioxide bleaching prior to hydrogen peroxide bleaching greatly improves the performance of the hydrogen peroxide stage. The efficiency is further improved by a chelating treatment immediately after the ozone or chlorine dioxide stage. With an optimal metal ion profile, laboratory bleached (OAZQP) softwood kraft pulps can reach brightness levels above 90% ISO, with 5-10% lower pulp strength properties and bleaching costs comparable to ECF bleaching. It also is possible to obtain full brightness with only hydrogen peroxide provided the metal ion profile is optimal, e.g., by using multiple QP treatments. The chemical consumptions, expressed as oxidation equivalents per decreased kappa number are the same as for sequences including ozone or chlorine dioxide. Ozone and chlorine dioxide are comparable as far as delignification and brightness efficiency go.
Place, publisher, year, edition, pages
1996. Vol. 79, no 1, 113-119 p.
Polymer Technologies Polymer Chemistry
IdentifiersURN: urn:nbn:se:kth:diva-80520OAI: oai:DiVA.org:kth-80520DiVA: diva2:498105
NR 201408052012-02-112012-02-092012-02-11Bibliographically approved