Methods for removing hemicellulose
AssigneeCelanese International Corporation
InventorsRongfu Li, Jay Mehta, Xiaoyan Tu, Prabuddha Bansal, Michael Combs, Denis Fallon, Lawton E Kizer
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Abstract
A method for treating a cellulosic material comprising extracting the cellulosic material with an extractant to selectively extract hemicellulose therein and separating the extracted hemicellulose to form a cellulosic product comprising less hemicellulose than the cellulosic material. The extractant comprises an amine oxide and a non-solvent. The cellulosic product retains the cellulosic fiber morphology.
Claims44
A method for treating a cellulosic material, comprising:
- extracting the cellulosic material with an extractant to selectively extract hemicellulose, wherein the extractant comprises an ionic liquid and a non-solvent;
- and
- separating the extracted hemicellulose from the cellulosic material to form a cellulosic product comprising less hemicellulose than the cellulosic material;
- wherein less than 15% of the cellulose in the cellulosic material is extracted.
A method for producing high purity α-cellulose grade pulp, comprising:
- extracting hemicellulose from a wood pulp by treating the wood pulp with an extractant comprising an ionic liquid and a non-solvent to form an intermediate wood pulp that retains a cellulosic fiber morphology;
- treating the intermediate wood pulp with an enzyme to hydrolyze hemicellulose contained therein and forming a reduced hemicellulose wood pulp;
- and
- washing the reduced hemicellulose wood pulp with a wash solution to form the high purity α-cellulose grade pulp;
- wherein less than 15% of the cellulose in the cellulosic material is extracted.
A high purity α-cellulose grade pulp product purified by removing hemicellulose from cellulosic material using a mixture of ionic liquid, water and enzyme, wherein the high purity α-cellulose grade pulp product comprises less than 5% hemicellulose;
- and wherein less than 15% of the cellulose in the cellulosic material is removed.
Dependencies are inferred from the claim text.