Methods for integrating the production of cellulose nanofibrils with the production of cellulose nanocrystals
AssigneeThe United States of America as represented by the Secretary of Agriculture
InventorsJunYong Zhu, Richard S. Reiner
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Abstract
Methods for integrating the production of cellulose nanocrystals (CNC) and cellulose nanofibrils (CNF) from cellulose are provided. The methods use milder acid hydrolysis conditions than those for maximal CNC production to achieve reduced degradation of cellulose into soluble sugars. Also provided are negatively charged cellulosic solid residues (CSRs) in the form of cellulose fibers (CF) and/or cellulose microfibrils (CMF) during the acid hydrolysis, as well as CNFs fabricated from the CSRs.
Claims19
A material comprising at least 50 wt. %, based on a solid content of the material, of cellulose particles, wherein the cellulose particles comprise surface ester functionalities and are selected from the group consisting of cellulose fibers, cellulose microfibers and cellulose nanofibrils.
A method for the production of cellulose nanofibrils from cellulosic solids comprising cellulose fibers, cellulose microfibers, or a combination thereof, the method comprising subjecting the cellulosic solids to mechanical shear forces, whereby the cellulose nanofibrils are formed and further wherein the cellulose fibers, cellulose microfibers and cellulose nanofibrils comprise surface ester functionalities.
A method for the production of cellulose nanofibrils from a cellulosic material comprising crystalline cellulosic components and amorphous cellulosic components, the method comprising:
- (a) hydrolyzing amorphous cellulosic components in the cellulosic material via an acid hydrolysis to obtain a cellulosic solid comprising cellulose nanocrystals and cellulosic solid residues, the cellulosic solid residues comprising cellulose fibers, cellulose microfibers, or a combination thereof;
- (b) separating the cellulose nanocrystals from the cellulosic solid residues;
- and
- (c) subjecting the cellulosic solid residues to mechanical shear forces, whereby the cellulose nanofibrils are formed.
Dependencies are inferred from the claim text.