	US 12,435,160 B2
	Separation of polycotton blends
Ali Harlin, Espoo (FI); Sakari Siren, Espoo (FI); and Jani Mäkelä, Espoo (FI)
Assigned to Infinited Fiber Company, Espoo (FI)
Appl. No. 17/910,377
Filed by Infinited Fiber Company Oy, Espoo (FI)
PCT Filed Mar. 9, 2021, PCT No. PCT/FI2021/050171 § 371(c)(1), (2) Date Sep. 9, 2022, PCT Pub. No. WO2021/181007, PCT Pub. Date Sep. 16, 2021.
Claims priority of application No. 20205250 (FI), filed on Mar. 9, 2020.
Prior Publication US 2023/0132641 A1, May 4, 2023
Int. Cl. C08B 15/06 (2006.01); C08B 16/00 (2006.01); D01F 2/02 (2006.01); D21C 5/00 (2006.01); D21C 9/00 (2006.01)

CPC C08B 15/06 (2013.01) [C08B 16/00 (2013.01); D01F 2/02 (2013.01); D21C 5/00 (2013.01); D21C 9/002 (2013.01)]

30 Claims

1. A method for recycling cellulose from a mixed fibre textile material comprising cellulosic and non-cellulosic fibres, said method comprising:

mechanically disintegrating the mixed fibre textile material by shredding, grinding, grating or milling the mixed fibre textile material to open textile structures in the material;

contacting the disintegrated textile material with an acid in a first chemical step to obtain acid-treated fibres; and

contacting the acid-treated fibres with an alkali in a second chemical step,

wherein the acid is selected from the group consisting of H₂SO₄, persulphuric acid, formic acid, acetic acid, performic acid, an acidic side stream of an industrial process, and mixtures thereof, and

wherein the first chemical step decreases the degree of polymerization of the cellulosic fibres by more than 10%.