MD simulations of solvated lignin fragments in the context of Kraft cooking and moisture actuation of compression wood

SNIC 2022/22-1163


SNIC Small Compute

Principal Investigator:

Klara Hackenstrass


Uppsala universitet

Start Date:


End Date:


Primary Classification:

10403: Materials Chemistry




Lignin is a biopolymer with a heterogenous structure, that is one of the main components of wood. In the plant it is important for the stability and water transport seemingly adapting its structure to the specific need of different plant tissues. One of these adaptations can be seen in compression wood (CW), a type of reaction wood that stabilizes leaning stems or branches. In CW the chemical structure of lignin is different compared to normal wood (NW), as well as showing changes on the cell level. Studying and understanding the differences could help the forestry industry dealing with the nowadays seen as inferior wood as well as inspire the design of new materials. Another context is the delignification in kraft cooking aiming at obtaining wood pulp containing mainly cellulose. This is done by cooking wood chips with sodium hydroxide and sodium sulfite, removing lignin and other components from the chips. Understanding the properties of lignin segments will help improve the efficiency of the process in terms of energy and biomass. In this project, Molecular Dynamics (MD) simulations of lignin fragments in a solvent are performed. The information gained from the simulations will provide parameters and insights on an atomistic level. Some of these will be used in a continuous model, that will allow to combine different size scales. The aim of the projects is to develop atomistic models of lignin and its interaction with water providing properties such as radius of gyration, hygroexpansion and structural flexibility. The project focussing on the delignification in the kraft cooking is funded by Vinnova and part of treesearch.