On October 21, 2024, Muhib Al-Rawi presented research titled “Kraft Lignin Solubility in Deep Eutectic Solvents,” under the supervision of Dr. Paulo Ribeiro Claro and Dr. Mariela Nolasco.

In this study, the ability of DES based on cholinium chloride (ChCl) combined with alcohols and carboxylic acids as hydrogen bond donors to dissolve kraft lignin is examined. The main goal is to get insights on the importance of the water content on the solubility of kraft lignin in DES. A computational spectroscopy approach, based on DFT calculations combined with inelastic neutron scattering [2,3], is applied to unravel the DES-water-lignin interactions at a molecular level, leading to a more comprehensive picture of the dissolution mechanism. Particular attention will be given to ChCl:1,6-hexanediol DES, due to its solubility properties. While for some DES systems, water addition reduces the lignin solubility, in the case of ChCl+1,6-hexanediol DES the high solubility is kept even at 50% wt water content.