Record Details
A new procedure for the determination of holocellulose
ScholarsArchive at Oregon State University
| Field | Value |
|---|---|
| Title | A new procedure for the determination of holocellulose |
| Names |
Swelim, Ahmed Abdel-Moniem
(creator) Kurth, E. F. (advisor) |
| Date Issued | 1963-02-25 (iso8601) |
| Note | Graduation date: 1963 |
| Abstract | The preparation of holocellulose accurately and rapidly is very important to study the nature and relationships of the carbohydrate components and the substituent groups, acetyl, carboxyl, and methoxyl. In as much as bromine was thought to be less destructive to wood than chlorine, it was decided to attempt to isolate the holocellulose quantitatively from wood by using bromine. In addition, it was decided to study the bromination reaction of wood under different conditions. Because delignification of wood with bromine depends on many factors such as time of each bromination, temperature of the basic solution, concentration of the basic solution, number of brominations and extractions, bromine concentration and the effect of an ice-water jacket, it was decided to study and investigate these factors in full detail. A summary of the results obtained is as follows: 1. A new procedure for holocellulose determination by using bromine for delignification of wood was developed. The results obtained by the new procedure agreed within one percent with the theoretical value. 2. Bromolignin samples were prepared by the action of bromine on moist wood samples. The solubility of bromolignins was examined in different solvents. Of those used, it was found that 1, 4 dioxane was the best solvent for the bromolignins. 3. Five minute intervals for each bromination were found to be the most suitable time for a quantitative yield of holocellulose. 4. The temperature of the basic solution was found to be 70°C, since this was the most effective temperature to obtain delignification of the sample with minimum degradation. 5. The concentration of the basic solution was found to be five percent monoethanolamine in 1, 4 dioxane. 6. The number of brominations and extractions necessary for complete delignification of wood was found to be nine for Douglas-fir (soft wood) and four for Black Oak (hard wood). 7. The use of elemental bromine was necessary for complete deligniation of wood. Two milliliters of bromine per one gram wood sample were needed for each bromination. 8. The use of an ice-water jacket found necessary in other procedures was omitted in this procedure and the reaction was performed quantitatively at room temperature. |
| Genre | Thesis/Dissertation |
| Topic | Cellulose |
| Identifier | http://hdl.handle.net/1957/49106 |
