New approach for the production of cellulose acetate: acetylation of mechanical pulp with subsequent isolation of cellulose acetate by differential solubility

Thesis/Dissertation · Thu Jan 01 00:00:00 EST 1987

OSTI ID:5495927

Barkalow, D G

A heretofore uninvestigated approach to the production of cellulose acetate is the acetylation of mechanical pulp with subsequent isolation of the cellulose derivative by differential solubility. The mechanical pulp is produced by refining aspen wood chips in a disc-refiner. Two conventional acetylation techniques, the fibrous and solution process, are employed to acetylate all components of the pulp. The cellulose acetate is isolated from the acetylated lignin and hemicellulose by dissolving in dichloromethane/methanol (9:1, v/v). The advantage of this new approach is that the high costs involved in using an extensively purified dissolving pulp are avoided. Both procedures yield a product that is about 84% cellulose acetate. The remaining acetylated components are lignin and hemicellulose. The average lignin content of the product from the solution process is 3.5% (1.5-4.7% range), and for the fibrous process it is 3.4% (1.2-5% range). The hemicellulose component averages 5.8% (2.5-9.1% range) for the solution process and 6.5% (3.0-8.7% range) for the fibrous process. The yield of cellulose acetate, based on the cellulose content of the original pulp and the product, is 75% for the solution process and 75-80% for the fibrous process. The cellulose acetate degree of polymerization (DP) is dependent on the sulfuric acid catalyst concentration, and on the reaction time in the case of the solution process. The product can be produced with a weight average DP from 1853 to 65 for the solution process, and 980 to 284 for the fibrous process. Applications for the product include lacquers, plastic films, and packaging.

• Research Organization: Wisconsin Univ., Madison (USA)
• OSTI ID: 5495927
• Resource Relation: Other Information: Thesis (Ph. D.)
• Country of Publication: United States
• Language: English

Related Subjects

09 BIOMASS FUELS
CELLULOSE ESTERS
PRODUCTION
WOOD
ACETYLATION
ASPENS
CHEMICAL REACTION YIELD
HEMICELLULOSE
LIGNIN
ORGANIC SOLVENTS
POLYMERIZATION
SEPARATION PROCESSES
SLURRIES
SOLUBILITY
SULFURIC ACID
TIME DEPENDENCE
ACYLATION
CARBOHYDRATES
CHEMICAL REACTIONS
DISPERSIONS
ESTERS
HYDROGEN COMPOUNDS
INORGANIC ACIDS
MIXTURES
ORGANIC COMPOUNDS
PLANTS
POLYSACCHARIDES
SACCHARIDES
SOLVENTS
SUSPENSIONS
TREES
YIELDS
140504* - Solar Energy Conversion- Biomass Production & Conversion- (-1989)