Method for producing porous cellulose medium

Patent metadata

Field	Value
Publication number	US-11097251-B2
Application number	US-201716097924-A
Country	US
Kind code	B2
Filing date	May 12, 2017
Priority date	May 13, 2016
Publication date	Aug 24, 2021
Grant date	Aug 24, 2021

Abstract

Provided is a novel method by which a porous cellulose medium is able to be suitably produced from cellulose acetate. A method for producing a porous cellulose medium, which comprises: a step for preparing a cellulose acetate solution wherein cellulose acetate is dissolved in a solvent; and a step for obtaining a mixed solution by mixing the cellulose acetate solution, a deacetylating agent and a catalyst with each other.

First claim

The invention claimed is:

1. A method for producing a porous cellulose medium, the method comprising the steps of:
preparing a cellulose acetate solution with cellulose acetate dissolved in a solvent;
mixing the cellulose acetate solution, a deacetylating agent, and a catalyst to obtain a mixed solution; and
stirring the mixed solution to maintain the components in dissolved form until deacetylation of the cellulose acetate proceeds;
wherein, in the mixed solution, deacetylation of the cellulose acetate proceeds, leading to occurrence of a liquid-gel phase transition.

2. The method for producing a porous cellulose medium according to claim 1 , wherein the catalyst is at least one selected from the group consisting of an alkoxide, an amine compound, a weak-basic inorganic compound, and a N-hydroxyamine derivative.

3. The method for producing a porous cellulose medium according to claim 2 , wherein the amine compound is a tertiary amine, and the weak-basic inorganic compound is a carbonate.

4. The method for producing a porous cellulose medium according to any one of claims 1 to 3 , wherein a porous cellulose monolith formed from the porous cellulose medium is obtained by allowing a deacetylation reaction of the cellulose acetate to proceed in a state in which the mixed solution is left standing in a molding container.

5. The method for producing a porous cellulose medium according to claim 1 , wherein porous cellulose particles formed from the porous cellulose medium are obtained by mixing the mixed solution with a dispersion medium immiscible with the mixed solution, and allowing a deacetylation reaction of the cellulose acetate to proceed in a state in which the mixed solution is dispersed.

6. The method for producing a porous cellulose medium according to claim 5 , wherein the dispersion medium is liquid paraffin.

7. The method for producing a porous cellulose medium according to claim 1 , wherein the catalyst comprises at least one of an alkoxide and a N-hydroxyamine derivative.

8. The method for producing a porous cellulose medium according to claim 1 , wherein the deacetylating agent comprises at least one of an alcohol, an amine, an amino alcohol, and water.

9. The method for producing a porous cellulose medium according to claim 1 , wherein the deacetylating agent comprises an amine.

10. The method for producing a porous cellulose medium according to claim 1 , wherein the deacetylating agent comprises at least one of aliphatic monohydric alcohols having 1 to 4 carbon atoms, aromatic alcohols, polyhydric alcohols having 2 to 6 carbon atoms, monomethyl ethers, and monoethyl ethers.

11. The method for producing a porous cellulose medium according to claim 1 , wherein the deacetylating agent comprises at least one of ammonia, aliphatic primary amines having 1 to 5 carbon atoms, aliphatic secondary amines having 1 to 5 carbon atoms, diamines, and benzylamines.

12. The method for producing a porous cellulose medium according to claim 1 , wherein the deacetylating agent comprises at least one of 2-aminoethanol and 3-aminopropanol.

13. The method for producing a porous cellulose medium according to claim 1 , wherein the deacetylating agent is methanol and the catalyst is potassium carbonate.

Assignees

• Daicel Corp

Inventors

• Shibata Toru
• Hirabayashi Yuki

Classifications

• B01J20/30

  Processes for preparing, regenerating, or reactivating · CPC title

• B01J20/24 Primary

  Naturally occurring macromolecular compounds, e.g. humic acids or their derivatives · CPC title

• B01J20/3085

  Chemical treatments not covered by groups B01J20/3007 - B01J20/3078 · CPC title

• B01J20/28019

  Spherical, ellipsoidal or cylindrical · CPC title

• B01D15/3809

  of the antigen-antibody type, e.g. protein A, G or L chromatography · CPC title