Pretreatment methods for cotton textile waste fabric

Patent metadata

Field	Value
Publication number	US-12351983-B2
Application number	US-202218062384-A
Country	US
Kind code	B2
Filing date	Dec 6, 2022
Priority date	Dec 8, 2021
Publication date	Jul 8, 2025
Grant date	Jul 8, 2025

Abstract

Disclosed is mechanical and decolorization pretreatment of cotton-containing textiles, such as “trash” feedstock in terms of end-of-life-cotton textiles, that may be used to produce sugar without the use of harsh pretreatments conditions.

First claim

The invention claimed is:

1. A method of pretreating cotton-containing textile material comprising refining the cotton-containing textile material in a PFI mill for between about 2,000 and 20,000 revolutions,
wherein the method does not comprise a pretreatment step that requires neutralization from use of an acid or base, recovery of any solvent, or rinsing steps necessitated from a pretreatment that requires components to be removed before hydrolysis and/or fermentation.

2. The method of claim 1 , wherein the method further comprises pretreatment comprising mechanical pretreatment, chemical, enzymatic pretreatment, or a combination thereof.

3. The method of claim 2 , wherein the mechanical pretreatment is substantially free of the use of chemicals.

4. The method of claim 2 , wherein the mechanically pretreated cotton-containing textile material comprises between about 1% and 50% fines by weight.

5. The method of claim 2 , wherein the fiber length LWL (mm) of the mechanically pretreated cotton-containing textile material is between about 0.1 mm and 2.00 mm.

6. The method of claim 2 , wherein the Canadian Standard Freeness (CSF) of mechanically pretreated cotton-containing textile material is between about 100 and 900 CSF milliliters.

7. The method of claim 2 , wherein the mechanically pretreated cotton-containing textile is in the form of a powder.

8. The method of claim 2 , wherein a Wiley Mill is used for the cutting step.

9. The method of claim 2 , wherein the mechanical pretreatment is performed before decolorization of the cotton-containing textile material.

10. The method of claim 1 , wherein the method further comprises shredding the cotton-containing textile material, cutting the cotton-containing textile material, and milling the cotton-containing textile material prior to refining the cotton-containing textile material in PFI mill.

11. The method of claim 1 , wherein a solvent is added to the cotton-containing textile material prior to refining in a PFI mill.

12. The method of claim 11 , wherein the solvent is water.

13. The method of claim 11 , wherein the solvent is added before, during, or both before and during refining.

14. The method of claim 1 , wherein the method further comprises enzymatic hydrolysis of the pretreated cotton-containing textile material to produce a hydrolysate.

15. The method of claim 1 , wherein the method further comprises decolorizing the cotton-containing textile material.

16. The method of claim 15 , wherein the decolorizing step comprises bleaching.

17. The method of claim 1 , wherein the method further comprises adding Cu 2+ .

18. The method of claim 1 , wherein the method further comprises adding Fe 2+ .

19. The method of claim 1 , wherein the level of refining is between about 2,000 and 20,000 PFI revs.

20. The method of claim 1 , wherein the method further comprises subjecting the pretreated cotton-containing textile material to hydrolysis to produce a hydrolysate.

21. The method of claim 20 , wherein the hydrolysis comprises enzyme hydrolysis comprising the addition of at least one hydrolytic enzyme.

22. The method of claim 21 , wherein the enzyme hydrolysis comprises the addition combination of a cellulase and a β-glucosidase.

23. The method of claim 20 , wherein the method further comprises subjecting the hydrolysate to fermentation to produce an end product.

24. The method of claim 23 , wherein the end product produced by fermentation comprises alcohols, sugar alcohols, acids, fatty acids, gases, amino acids, chemicals, and mixtures thereof.

25. The method of claim 1 , wherein the method does not comprise a step that requires the use of an acid.

26. The method of claim 1 , wherein the cotton-containing textiles comprise cotton, cotton-blend garments, cotton-polyester blend garments, or mixtures thereof.

27. A method of processing cotton-containing textile material comprising
(a) shredding the cotton-containing textile material;
(b) cutting the cotton-containing textile material;
(c) milling the cotton-containing textile material;
(d) refining the cotton-containing textile material in a PFI mill for between about 2,000 and 20,000 revolutions; and
(e) subjecting the cotton-containing textile material to hydrolysis to produce a hydrolysate,
wherein the method does not comprise a pretreatment step that requires neutralization from use of an acid or base, recovery of any solvent, or rinsing steps necessitated from a pretreatment that requires components to be removed before hydrolysis and/or fermentation.

28. The method of claim 27 , wherein the cotton-containing textiles comprise cotton, cotton-blend garments, cotton-polyester blend garments, or mixtures thereof.

Assignees

• Univ North Carolina State
• Cotton Inc

Inventors

• Ankeny Mary Ann
• Farrell Matthew J
• Gonzalez Ronalds
• Jameel Hasan

Classifications

• D21D1/40

  Washing the fibres · CPC title

• D21H17/67 Primary

  Water-insoluble compounds, e.g. fillers, pigments · CPC title

• D21B1/14 Primary

  Disintegrating in mills · CPC title

• D21C5/005

  Treatment of cellulose-containing material with microorganisms or enzymes · CPC title

• D21C5/00

  Other processes for obtaining cellulose, e.g. cooking cotton linters (obtaining fibres for spinning D01C); {Processes characterised by the choice of cellulose-containing starting materials} · CPC title