Granted Patent B2

US 12,709,648 · App. 18/392,146 · Granted Aug 18, 2026

Inventors: Elsayed Adbelfatah (Shelton, CT); Alejandra Enriquez (Calgary, CA); Markus Weissenberger (Calgary, CA)

Assignee: SixRing Inc.

C08B15/02C08B1/00C08L1/04

Abstract

Claims (94)

1 . A process to manufacture nanocrystalline cellulose from a cellulose having a low hemicellulose content, said process comprising the steps of:

exposing said cellulose to a solution comprising a microemulsion for a first pre-determined period of time, thereby creating a soaked cellulose;

optionally, exposing the soaked cellulose to a sonication step for a second predetermined period of time; and

exposing the resulting mixture to a source of peroxide with a metal salt selected from the group consisting of: FeSO 4 or CuSO 4 under acidic conditions for a third pre-determined period causing hydrolysis of the cellulose; and

recovering the resulting nanocrystalline cellulose,

wherein the starting cellulose has a particle size ranging from 100 to 1000 μm.

2 . The process according to claim 1 , wherein the nanocrystalline cellulose will have a crystallinity index of more than 50% and an aspect ratio ranging from 10:1 length to width to 50:1 length to width.

3 . The process according to claim 1 , wherein said microemulsion composition comprises:

water;

a solvent;

a nonionic surfactant;

a hydrophobic component.

4 . The process according to claim 3 , where the solvent is selected from the group consisting of: ethanol; methanol; isopropanol; propanol and other short chain alcohols.

5 . The process according to claim 3 , where the nonionic surfactant is selected from the group consisting of alcohol ethoxylates and/or alkyl polyglucosides.

6 . The process according to claim 3 , where the hydrophobic component is selected from the group consisting of mineral oil, silicon oil, paraffin oil, and pale oil or a terpene.

7 . The process according to claim 3 , where an inorganic and/or organic base is added to the microemulsion; where said base is selected from the group consisting of: sodium hydroxide, potassium hydroxide, ammonium hydroxide and alkanolamines and combinations thereof.

8 . The process according to claim 4 , where the hydrophobic component is present in the composition in an amount ranging from 0.1 wt. % to 20% wt.

9 . The method according to claim 4 , where the hydrophobic component is present in the composition in an amount ranging from 1 wt. % to 15% wt.

10 . The method according to claim 4 , where the solvent is present in the composition in an amount ranging from 0.1 wt. % to 20% wt.

11 . The method according to claim 4 , where the microemulsion composition is added to the water in a concentration ranging from 0.1 to 90% wt.

12 . A process to manufacture nanocrystalline cellulose from cellulose having a low lignin and low hemicellulose content, said process comprising the steps of:

exposing said cellulose to a microemulsion composition for a first pre-determined period of time, thereby creating a soaked cellulose;

optionally, exposing the soaked cellulose to a sonication step for a second predetermined period of time;

exposing the resulting mixture to a source of peroxide with a metal salt selected from the group consisting of: FeSO 4 or CuSO 4 under acidic conditions, for a third pre-determined period causing hydrolysis of the cellulose; and

recovering the resulting nanocrystalline cellulose.

13 . A method for the preparation of nanocrystalline cellulose from a biomass, where said method comprises the following steps:

providing a biomass feedstock comprising: cellulose; hemicellulose; and lignin;

exposing the biomass to a modified Caro's acid selected from the group consisting of:

composition A; composition B and composition C;

wherein said composition A comprises:

sulfuric acid in an amount ranging from 20 to 70 wt % of the total weight of the composition;

a compound comprising an amine moiety and a sulfonic acid moiety selected from the group consisting of: taurine; taurine derivatives;

and taurine-related compounds; and

a peroxide;

wherein said composition B comprises:

an alkylsulfonic acid; and

a peroxide; wherein the acid is present in an amount ranging from 40 to 80 wt % of the total weight of the composition and where the peroxide is present in an amount ranging from 10 to 40 wt % of the total weight of the composition;

wherein said composition C comprises:

sulfuric acid;

a compound comprising an amine moiety;

a compound comprising a sulfonic acid moiety; and

a peroxide;

to create a biomass/acid mixture;

allow exposure for a period of time sufficient to dissolve enough of the lignin present in said biomass mixture to obtain a kappa number for the cellulose of less than 10;

separating the liquid from the solid portion of delignification mixture;

optionally, exposing the solid portion to a caustic composition to dissolve the hemicellulose present therein;

extracting the remaining cellulose;

optionally, adjusting the pH of the cellulose;

exposing said cellulose to a microemulsion composition for a first pre-determined period of time, thereby creating a soaked cellulose;

optionally, exposing the soaked cellulose to a sonication step for a second predetermined period of time;

exposing the resulting mixture to a source of peroxide with a metal salt selected from the group consisting of: FeSO 4 or CuSO 4 , for a third pre-determined period causing hydrolysis of the cellulose; and

recovering the resulting nanocrystalline cellulose.

14 . A method for increasing the yield of nanocrystalline cellulose from a cellulose having a low hemicellulose content, said process comprising the steps of:

exposing said cellulose to a solution comprising a microemulsion for a first pre-determined period of time, thereby creating a soaked cellulose;

optionally, exposing the soaked cellulose to a sonication step for a second predetermined period of time; and

exposing the resulting mixture to a source of peroxide with a metal salt selected from the group consisting of: FeSO 4 or CuSO 4 , under acidic conditions for a third pre-determined period causing hydrolysis of the cellulose; and

recovering the resulting nanocrystalline cellulose;

wherein the starting cellulose has a particle size ranging from 100 to 1000 μm.

15 . The method of claim 14 , wherein said cellulose is obtained from a biomass, where said method comprises the following steps:

providing a biomass feedstock comprising: cellulose; hemicellulose; and lignin;

exposing the biomass to a modified Caro's acid selected from the group consisting of:

composition A; composition B and Composition C;

wherein said composition A comprises:

sulfuric acid in an amount ranging from 20 to 70 wt % of the total weight of the composition;

a compound comprising an amine moiety and a sulfonic acid moiety selected from the group consisting of: taurine; taurine derivatives;

and taurine-related compounds; and

a peroxide;

wherein said composition B comprises:

an alkylsulfonic acid; and

a peroxide; wherein the acid is present in an amount ranging from 40 to 80 wt % of the total weight of the composition and where the peroxide is present in an amount ranging from 10 to 40 wt % of the total weight of the composition;

wherein said composition C comprises:

sulfuric acid;

a compound comprising an amine moiety;

a compound comprising a sulfonic acid moiety; and

a peroxide;

to create a biomass/acid mixture;

allow exposure for a period of time sufficient to dissolve enough of the lignin present in said biomass mixture to obtain a kappa number for the cellulose of less than 10;

separating the liquid from the solid portion of delignification mixture;

optionally, exposing the solid portion to a caustic composition to dissolve the hemicellulose present therein;

extracting the remaining cellulose; and

optionally, adjusting the pH of the cellulose.

16 . The method according to claim 14 , wherein said microemulsion composition comprises:

water;

a solvent;

a nonionic surfactant;

a hydrophobic component.

17 . The method according to claim 16 , where the solvent is selected from the group consisting of: ethanol; methanol; isopropanol; propanol and other short chain alcohols.

18 . The method according to claim 16 , where the nonionic surfactant is selected from the group consisting of alcohol ethoxylates and/or alkyl polyglucosides.

19 . The method according to claim 16 , where the hydrophobic component is selected from the group consisting of mineral oil, silicon oil, paraffin oil, and pale oil or a terpene.

20 . The method according to claim 16 , where an inorganic and/or organic base is added to the microemulsion; where said base is selected from the group consisting of: sodium hydroxide, potassium hydroxide, ammonium hydroxide and alkanolamines, and combinations thereof.

21 . The method according to claim 16 , where the hydrophobic component is present in the composition in an amount ranging from 0.1 wt. % to 20% wt.

22 . The method according to claim 16 , where the hydrophobic component is present in the composition in an amount ranging from 1 wt. % to 15% wt.

23 . The method according to claim 16 , where the solvent is present in the composition in an amount ranging from 0.1 wt. % to 20% wt.

24 . The method according to claim 16 , where the microemulsion composition is added to the solution in a concentration ranging from 0.1 to 90% wt.

Assignments (1)

Priority Claims (1)

Continuity (1)

References Cited (95)