Effect of Topological Structure of Cellulose on the Processes of Acetylation and Nitration
Journal Title: Lesnoy Zhurnal (Russian Forestry Journal) - Year 2023, Vol 6, Issue 6
Abstract
Cellulose esters are actively used in the production of new by-products, drugs, and materials. Plant raw materials are the main source for the production of cellulose derivatives. The production of cellulose by microbial synthesis is also becoming promising. Despite similar pathways of microfibril biosynthesis, cellulose samples of plant and bacterial origin differ in a number of structural features. The aim of this work is to evaluate the influence of the topological structure of cellulose of plant and bacterial origin on the acetylation and nitration processes. Cotton and kraft cellulose were used as samples of plant cellulose. Bacterial cellulose was obtained in the laboratory using a mixed community of microorganisms under static conditions on synthetic glucose media. Nitration of cellulose samples was carried out with a mixture of concentrated sulfuric and nitric acids; and the degree of substitution was calculated from the nitrogen content determined by the ferrosulfate method. The IR spectra of samples of the original cotton cellulose, as well as nitrates of bacterial and cotton cellulose, were recorded on a Vertex-70 infrared Fourier spectrometer in the range of wave numbers 4000â¦400 cmâ1. Cellulose acetylation was carried out in supercritical carbon dioxide by direct acetylation in an SFE-5000 supercritical fluid extraction system, Thar Process. The content of bound acetic acid in cellulose acetate was determined titrimetrically and then the degree of substitution was calculated. Fibers of plant cellulose and fibrils of bacterial cellulose were visualized by electron and atomic force microscopy. The yield of nitrate from pure cotton cellulose was 160 %, i.e., the degree of substitution was 2.20. Cellulose nitrate obtained from bacterial cellulose under similar conditions had a degree of substitution of 1.96. A new method of direct acetylation of lyophilically dried preparations of bacterial cellulose in supercritical carbon dioxide was proposed, which allows the process to be carried out without acid catalyst and at reduced consumption of acetylating agent. Acetylation of plant kraft cellulose showed a degree of substitution of 2.40, for bacterial cellulose â yield of diacetyl cellulose with the content of acetyl groups 50 %, this corresponds to the degree of substitution of 2.10. The obtaining of esters is due to both topochemical features of microfibrils and crystallinity of the material. For citation: Vashukova K.S., Terentyev K.Y., Chukhchin D.G., Ivakhnov A.D., Poshina D.N. Effect of Topological Structure of Cellulose on the Processes of Acetylation and Nitration. Lesnoy Zhurnal = Russian Forestry Journal, 2023, no. 6, pp. 176â189. (In Russ.). https://doi.org/10.37482/0536-1036-2023-6-176-189
Authors and Affiliations
Ðsenia S. Vashukova,Konstantin Y. Terentyev,Dmitry G. Chukhchin,Artem D. Ivakhnov,Daria N. Poshina,
Keywords
Related Articles
- EP ID EP725348
- DOI 10.37482/0536-1036-2023-6-176-189
- Views 30
- Downloads 0
Efficiency of Thinning in Deciduous-Spruce Forest Stands in the Northern Taiga Forest Region of the European Part of the Russian Federation
Research on permanent sample plots (Arkhangelsk, Northern district forestry, Obozerskoye forestry) in birch and spruce stands with an understory layer of spruce was carried out. The sample plots were established since 19...
Representatives of thePine Family (Pinaceae Lindl.) of the North American Flora in the Collection of the Dendrological Garden named after V.N. Nilov (NRIF)
The article presents the results of the introduction of the North American flora woody species of the pine family (Pinaceae Lindl.) to the European North of Russia. The research purpose is to select the most valuable spe...
Formation of Sectoral Residual Thermoplastic Tension Fields in Circular Saw Blade
The efficiency of a stationary circular saw is determined by the performance and operational reliability of the woodcutting unit. During operation, the circular saw blade is exposed to a variety of complex loads and ther...
Aerostatic aircraft for Logging in remote forest areas
The article analyzes the situation of the majority of logging enterprises in the Far Eastern region associated with the depletion of easily accessible forest areas, which can be developed by traditional logging methods u...
Functional Composition and Structural Features of Higher Plant Lignins
NMR spectroscopy is one of the effective methods for the study of plant raw materials, which makes it possible to identify differences in the structure and functional composition of lignins of various types of plant biom...