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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Production of acetic acid in kraft pulp mill biorefinery using bi-polar membrane electrodialysis

Patil, Ravikant Amogisidha 13 December 2016 (has links)
<p> The objective of this dissertation was to develop a process for the production of acetic acid in kraft mills. Acetyl groups in hardwood can be hydrolyzed using alkali at 50 &deg;C. The product from this process contains about 15 g/L of sodium acetate and was determined to be suitable for the production of acetic acid.</p><p> Experiments performed using aqueous sodium acetate to evaluate the ability of electrodialysis (ED) to separate and concentrate sodium acetate showed that sodium acetate can be concentrated up to 275 g/L starting with an initial concentration of 17 g/L. The transport of water with sodium and acetate ions through ED membranes limited the maximum obtainable concentration.</p><p> To avoid the deleterious effects of white liquor on ED, selectivity experiments were performed using synthetic oxidized white liquor extract. These experiments showed a decrease in the efficiency of ED process due to the presence of sodium carbonate and sodium sulphate in the extract. Hence, it was concluded that caustic should be used as the extraction solvent.</p><p> Bi-polar electrodialysis (BPMED) experiments performed using sodium acetate showed that up to 200-280 g/L of acetic acid can be produced using BPMED. Although higher concentrations of sodium hydroxide can also be produced using BPMED, 30 g/L concentration was considered to be sufficient for recycle to the extraction process.</p><p> Feed and bleed mode BPMED experiments were performed to determine the current efficiencies and the suitable inlet concentration of sodium acetate for the production of up to 200 g/L of acetic acid. Both feed and bleed mode and batch experiments showed that the current density was the major driving force for BPMED.</p><p> Two types of concentrated wood extracts; namely (1) clarified and (2) unclarified were prepared with and without the lignin removal pre-treatment, respectively. The results of the ED and BPMED experiments performed using these extracts were similar to those of the synthetic sodium acetate. A major difference involved an increase of about 15% in electric energy consumption arising from the transport of formate, lactate and glycolate salts. The color of the anionic membranes slightly changed after processing unclarified extract through ED and BPMED.</p>
2

The fate of the aglucone group in aqueous-chlorine oxidation of carbon-14 labeled methyl [beta]-D-glucopyranoside

Crossman, James K., January 1964 (has links) (PDF)
Thesis (Ph. D.)--Institute of Paper Chemistry, 1964. / Includes bibliographical references (leaves 67-70).
3

The papermaking properties of highly purified pulps

Probst, T. Richard January 1939 (has links) (PDF)
Thesis (Ph. D.)--Institute of Paper Chemistry, 1939. / Bibliography: leaves 97-100.
4

Mechanical treatment of pulp fibers for property development

Hartman, Richard R. January 1984 (has links) (PDF)
Thesis (Ph. D.)--Institute of Paper Chemistry, 1984. / Bibliography: leaves 74-77.
5

The Kinetics of the reactions involved in the bleaching of eastern spruce groundwood with alkaline peroxide

Martin, Darrell M. January 1951 (has links) (PDF)
Thesis (Ph. D.)--Institute of Paper Chemistry, 1951. / Includes bibliographical references (p. 221-223).
6

The alkaline hydrogen peroxide oxidation of phelyl-2-propanones

Jones, Drexel D., January 1966 (has links) (PDF)
Thesis (Ph. D.)--Institute of Paper Chemistry, 1966. / Includes bibliographical references (p. 102-106).
7

The influence of cooking and bleaching upon the chain length distribution of the carbohydrate fraction in pulp wood

Atchison, Joseph Edward, January 1942 (has links) (PDF)
Thesis (Ph. D.)--Institute of Paper Chemistry, 1942. / Includes bibliographical references (p. 97-99).
8

A study of the reaction products formed upon the alkaline peroxide oxidation of lignin-related model compounds

Reeves, R. Heath, January 1964 (has links) (PDF)
Thesis (Ph. D.)--Institute of Paper Chemistry, 1964. / Includes bibliographical references (p. 52-54).
9

An investigation of accelerated brightness reversion of bleached slash pine kraft pulp

Rollinson, Samuel Milton, January 1954 (has links) (PDF)
Thesis (Ph. D.)--Institute of Paper Chemistry, 1954. / Includes bibliographical references (p. 95-109).
10

The effect of bleaching on the optical characteristics of pulp

Forni, Pasquale A. January 1943 (has links) (PDF)
Thesis (Ph. D.)--Institute of Paper Chemistry, 1943. / Includes bibliographical references (leaves 96-98).

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