Nano-deaggregated cellulose

• US 9,187,571 B2
• Filed: 09/14/2011
• Issued: 11/17/2015
• Est. Priority Date: 04/03/2008
• Status: Active Grant

• Current Assignee: Cellulose Sciences International, Inc.
• Original Assignee: Cellulose Sciences International, Inc.
• Inventors: Atalla, Rajai H.
• Primary Examiner(s): HUG, JOHN ERIC
• Application Number:
  US13/822,190
• Publication Number:
  US 20130172544A1
• Time in Patent Office: 1,525 Days
• Field of Search: 162/146, 162/157.6, 162/9, 162/77, 162/90, 536/56, 536/57, 127/37
• US Class Current: 1/1
• CPC Class Codes: C08B 1/00 Preparatory treatment of cellulose for making derivatives thereof , e.g. pre-treatment, pre-soaking, activation
• CPC Class Codes: C08B 15/08 Fractionation of cellulose, e.g. separation of cellulose crystallites
• CPC Class Codes: C08L 1/02 Cellulose; Modified cellulose
• CPC Class Codes: C12P 19/14 produced by the action of a carbohydrase (EC 3.2.x), e.g. by alpha-amylase , e.g. by cellulase, hemicellulase
• CPC Class Codes: D21C 5/005 Treatment of cellulose-containing material with microorganisms or enzymes
• CPC Class Codes: D21H 17/005 Microorganisms or enzymes

Abstract

Disclosed are methods and systems for treating cellulose to make it more accessible for enzymatic or chemical modification. The invention includes treating cellulose with an alkali in an alcohol/water co-solvent system. The treatment decrystallizes or deaggregates the cellulosic material. The methods and systems increase the efficiency of enzymatic or chemical modifications of cellulose for use as biofuels or cellulose derivatives.

Claims

1. Nano-deaggregated cellulose, wherein the cellulose is water-stable and is not converted to cellulose II in aqueous media.

2. The nano-deaggregated cellulose of claim 1 having a x-ray pattern as shown in FIGS. 10-16 compared to untreated cellulosic substrates.

3. The nano-deaggregated cellulose of claim 1 having a Raman spectrum as shown in FIGS. 17-20 compared to untreated cellulosic substrates.

4. The nano-deaggregated cellulose of claim 1, further comprising dark opaque grain/cellular stains compared to transparent stains of cellulose I with Graff'"'"'s C stain.

5. The nano-deaggregated cellulose of claim 1, further comprising a greater enzymatic hydrolysis conversion to soluble saccharides than cellulose I at the same concentration of enzyme.

6. The nano-deaggregated cellulose of claim 5, wherein enzymatic hydrolysis conversion to soluble saccharides is at least 70%.

7. The nano-deaggregated cellulose of claim 5, wherein enzymatic hydrolysis conversion to soluble saccharides is at least 90%.

8. The nano-deaggregated cellulose of claim 1 having NMR spectra as shown in FIG. 21.

9. Nano-deaggregated cellulose having the following properties:

a) x-ray diffraction peaks at diffraction angle 2Θ

different from cellulose I, or cellulose II or amorphous cellulose as shown in FIGS. 10-16;

b) Raman spectral peaks different from cellulose I or cellulose II as shown in FIGS. 17-20;

c) NMR spectral peaks different from cellulose I or cellulose II as shown in FIG. 21;

d) stability in aqueous media;

e) a greater enzymatic hydrolysis to soluble saccharides than cellulose I or cellulose II at the same concentration of enzyme; and

f) a greater Graff'"'"'s C stain color intensity than cellulose I.

10. A composition comprising the nano-deaggregated cellulose of claim 9.

11. A pulp made of nano-deaggregated cellulosic fibers with the composition of claim 10.

12. A pulp made of nano-deaggregated cellulosic fibers with a composition comprising nano-deaggregated cellulose having the following properties:

a) x-ray diffraction peaks at diffraction angle 2Θ

different from cellulose I or cellulose II or amorphous cellulose as shown in FIGS. 10-16;

b) Raman spectral peaks different from cellulose I or cellulose II as shown in FIGS. 17-20;

c) NMR spectral peaks different from cellulose I or cellulose II as shown in FIG. 21;

d) stability in aqueous media;

e) a greater enzymatic hydrolysis to soluble saccharides than cellulose I or cellulose II at the same concentration of enzyme; and

f) a greater Graff'"'"'s C stain color intensity than cellulose I;

further comprising, as a handsheet compared to a cellulose I fibrous handsheet, a caliper, void volume and liquid retention which is twice that of the cellulose I hand sheet, and a Gurley porosity of 0.8 sec compared to 7 sec for the cellulose I handsheet.