A previously proposed kinetics equation describing the delignification of wood in soda-anthraquinone (AQ) liquors was shown to be valid under isothermal conditions, and was extended to describe variation in initial alkali charge. Kinetics expressions were derived for soda-amine, kraft (soda-hydrosulfide ion) and soda-ethanol delignification under isothermal conditions over various ranges of additive charge. In each case, the total delignification observed after a given time of pulping could be described as the sum or two contributions: (i) that due to the sodium hydroxide alone, and (ii) that due to the additive (AQ, amine, hydrosulfide ion or ethanol). Rate constants were determined at various temperatures and apparent Arrhenius activation energies were calculated for soda-AQ, soda-amine and kraft delignification. Although the calculated activation energies were found to be similar, the forms of kinetic expressions obtained suggested that the role of AQ in alkaline delignification may differ from that of an amine or hydrosulfide ion. The effects of various combinations of additive pairs on delignification were investigated and the results suggested that interactions occur. Under certain conditions, delignification in soda-AQ-amine and kraft-AQ liquors, respectively, could be described as the sum of the effects of the sodium hydroxide alone, the amine or hydrosulfide ion, and a term dependent upon the anthraquinone.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.68720 |
| Date | January 1982 |
| Creators | Rivers, J. A. (John Abbot) |
| Publisher | McGill University |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Format | application/pdf |
| Coverage | Doctor of Philosophy (Department of Chemistry) |
| Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
| Relation | alephsysno: 000138927, proquestno: AAINL10284, Theses scanned by UMI/ProQuest. |
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