A current key road block to the economic viability of a biorefinery is the inability to cost effectively separate biomass into lignin and cellulose. It has recently been reported that protic ionic liquids (PILs) can be used to extract lignin from lignocellulose to produce lignin-rich and cellulose-rich streams. However, the means by which the PIL (selectively) solubilises the lignin has not been explored. In this project we will elucidate interactions which promote the solubility of guaiacol (2-methoxyphenol) and hydroquinone (4-hydroxy-3-methoxybenzaldehyde) in ethylammonium nitrate (EAN) and ethylammonium hydrogen sulphate (EAHS). Comparison of the PIL nanostructures with and without added solute, and the favoured orientations of ions around the model solutes, will reveal the ion ¿ solute interactions that are key to the solubility of lignin-like materials in PILs.