Graduate Thesis Or Dissertation
 

Kraft pulping of Douglas-fir with soluble anthraquinone

Öffentlich Deposited

Herunterladbarer Inhalt

PDF Herunterladen
https://ir.library.oregonstate.edu/concern/graduate_thesis_or_dissertations/qn59q638k

Descriptions

Attribute NameValues
Creator
Abstract
  • Several additives have been used in research and on an industrial scale to improve the pulp yield and to increase the rate of delignification. One such additive is 1,4- dihydro- 9,10-dihydroxyanthracene (DDA), also called soluble anthraquinone. This chemical is widely used in Japan and some other countries, especially with the eucalyptus species; however, there is little information on this additive in the literature for pulping softwoods. The behavior of this chemical in the kraft pulping of Douglas-fir (Pseudotsuga menziesii), a predominant species of the northwest, was studied using DDA and the more common anthraquinone (AQ) additives. DDA was found to be a superior additive compared to AQ as the total pulp yields improved by 1 to 2% over AQ or 3 to 4% over control kraft, for kappa numbers below 90 (at 0.1% additive level). A decrease of 80 to 400 in the H-Factor is possible during cooking for pulps with kappa numbers between 25 and 80. For cooks producing pulps with kappa number of 90 or higher, DDA was actually detrimental. The brightness of the unbleached DDA pulps improved by 1 to 2% (TAPPI) over the AQ and control pulps. No significant difference was found in the beating performance of the three types of pulps and also there was no significant difference in the pulp viscosities or the strength properties of the handsheets made from these pulps.
Resource Type
Date Available
Date Issued
Degree Level
Degree Name
Degree Field
Degree Grantor
Commencement Year
Advisor
Academic Affiliation
Non-Academic Affiliation
Subject
Urheberrechts-Erklärung
Publisher
Peer Reviewed
Language
Digitization Specifications
  • File scanned at 300 ppi (Monochrome) using ScandAll PRO 1.8.1 on a Fi-6670 in PDF format. CVista PdfCompressor 4.0 was used for pdf compression and textual OCR.
Replaces

Beziehungen

Parents:

This work has no parents.

In Collection:

Artikel

Miniaturansicht Titel Hochladedatum Sichtbarkeit Aktionen
file details DuttaTapas1989.pdf 2017-08-07 Öffentlich Herunterladen