Processes for Purifying a Cellulosic Material

摘要

A process for treating a cellulosic material comprising extracting the cellulosic material with an extractant to selectively extract hemicellulose therefrom and separating the extracted hemicellulose to form a cellulosic product comprising less hemicellulose than the cellulosic material. The extractant comprises a cellulose solvent and a co-solvent. The cellulosic product advantageously retains its cellulosic fiber morphology. The processes involve separating and recovering the hemicellulose and separating and recycling various process streams employed in the process.

主权项

1. A process for purifying a cellulosic material, comprising:
extracting hemicellulose from the cellulosic material with an extractant to form an intermediate cellulosic material having a reduced hemicellulose content; concentrating the intermediate cellulosic material to form a concentrated cellulosic material having an increased solids content; and recovering the separated hemicellulose; wherein the extractant comprises a cellulose solvent and a co-solvent, and the cellulose solvent is selected from the group consisting of an ionic liquid, an amine oxide and combinations thereof.