Back to results
US 11,667,792 B2Granted
Process for preparing a solution of lignin in an aqueous medium
AssigneeStora Enso OYJ
InventorsAshar Zafar, Jesper Ekström
Life of this patent
Estimating the term…
Abstract
The present invention relates to a process for lignin dissolution in which partial methylolation of lignin is carried out during the step of preparing a solution of lignin in an aqueous medium comprising alkali. The lignin prepared according to the process of the present invention can be used to manufacture lignin-based phenolic resins, which are particularly useful in the manufacture of laminates.
Claims7
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.
1 more element
Dependencies are inferred from the claim text.