This project was about the regeneration of Deep Eutectic Solvent (DES) used in the pulping of wood.
After such pulping, the wood pulp containing the fibers for paper making are separated from the DES dark liquor by filtration. The DES dark liquor contains all chemicals released from the wood and which dissolved or stabilized in the DES phase. Before sending the DES back to pulping new wood, it is key to remove lignin and other chemicals. To what extent regeneration is necessary is not known yet, but aspect of ongoing research.
Targets
Develop sugar recovery approaches to valorize also the sugars in the DES dark liquor. For this, we aimed at:
- A membrane-based approach where the sugars should be retained
- An in-situ conversion approach to convert the sugars into furans or possibly even carboxylic acids such as levulinic acid
Next to the recovery of sugars from DES, also the recovery of lignin should be studied on larger scale in order to be able to isolate it. The larger scale lignin recovery studies have been done together with Suster BV. It was the aim to obtain various lignins and characterize them.