	US 11,667,792 B2
	Process for preparing a solution of lignin in an aqueous medium
Ashar Zafar, Alta (SE); and Jesper Ekström, Johanneshov (SE)
Assigned to Stora Enso OYJ, Helsinki (FI)
Appl. No. 16/613,738
Filed by Stora Enso OYJ, Helsinki (FI)
PCT Filed May 22, 2018, PCT No. PCT/IB2018/053597 § 371(c)(1), (2) Date Nov. 14, 2019, PCT Pub. No. WO2018/215922, PCT Pub. Date Nov. 29, 2018.
Claims priority of application No. 1750643-7 (SE), filed on May 23, 2017.
Prior Publication US 2020/0079960 A1, Mar. 12, 2020
Int. Cl. C08L 97/00 (2006.01); B27N 1/02 (2006.01); C08G 8/38 (2006.01)

CPC C08L 97/005 (2013.01) [B27N 1/0209 (2013.01); C08G 8/38 (2013.01)]

7 Claims

1. A method for dissolving lignin in an aqueous medium comprising the steps of

a) isolating lignin, and/or purifying the lignin;

b) mixing the lignin, alkali and formaldehyde in an aqueous medium;

c) mixing until a solution of the lignin in the aqueous medium has been obtained;

wherein the molar ratio between the formaldehyde and lignin monomer is in a range of from 0.01 to 0.2.