Process for manufacturing a fibrillated cellulose powder suitable for being dispersed in an aqueous medium

Patent metadata

Field	Value
Publication number	US-9969815-B2
Application number	US-201314410471-A
Country	US
Kind code	B2
Filing date	Jun 24, 2013
Priority date	Jun 25, 2012
Publication date	May 15, 2018
Grant date	May 15, 2018

Abstract

A method for manufacturing a fibrillated cellulose powder suitable for being dispersed in an aqueous medium, comprising a step of adding a monovalent salt (e.g., sodium chloride, potassium chloride, and lithium chloride) to a fibrillated cellulose suspension, followed by a lyophilization step to provide the fibrillated cellulose powder. Also disclosed are a method of dispersing the fibrillated cellulose powder comprising the method for manufacturing with the further steps of suspending the fibrillated cellulose powder in an aqueous medium and subsequent dialysis of the suspension.

First claim

The invention claimed is:

1. A method of dispersing a fibrillated cellulose powder, comprising:
adding ( 12 ) a monovalent salt selected from the group consisting of sodium chloride, potassium chloride, and lithium chloride to a suspension of fibrillated cellulose, followed by freeze drying ( 14 ) to provide the fibrillated cellulose powder;
incorporating said powder in an aqueous medium ( 20 ) to provide a suspension, followed by stirring ( 22 ) of the suspension; and
performing dialysis ( 26 ) on the suspension.

2. The method of claim 1 , wherein monovalent salt is added at a concentration in the range from 5 to 20 mmol/L.

3. The method of claim 1 , wherein the suspension of fibrillated cellulose comprises, by weight, from 1 to 3% of fibrillated cellulose.

4. The method of claim 1 , wherein the salt addition step is preceded by a step of pretreating the suspended fibrillated cellulose.

5. The method of claim 4 , wherein the pretreatment of the fibrillated cellulose is an enzyme or chemical pretreatment, for example, a carboxymethylation.

6. A method of dispersing a fibrillated cellulose powder, the method comprising:
adding ( 12 ) a monovalent salt to a suspension of fibrillated cellulose;
freeze drying ( 14 ) the combination of the monovalent salt and suspension of fibrillated cellulose to provide the fibrillated cellulose powder;
incorporating the fibrillated cellulose powder in an aqueous medium ( 20 ) to provide a suspension;
stirring ( 22 ) the suspension; and
performing a dialysis step ( 26 ) on the suspension.

Assignees

• Inst Polytechnique Grenoble

Inventors

• Bras Julien
• Belgacem Naceur
• Missoum Karim

Classifications

• C08B15/00 Primary

  Preparation of other cellulose derivatives or modified cellulose {, e.g. complexes} · CPC title

• C08B15/05

  Derivatives containing elements other than carbon, hydrogen, oxygen, halogens or sulfur (esters or phosphorous acids C08B5/00) · CPC title

• C08B1/00

  Preparatory treatment of cellulose for making derivatives thereof {, e.g. pre-treatment, pre-soaking, activation} · CPC title

• C08B15/02

  Oxycellulose; Hydrocellulose; {Cellulosehydrate, e.g. microcrystalline cellulose} · CPC title

• C08B15/08

  Fractionation of cellulose, e.g. separation of cellulose crystallites · CPC title