Solubility and rate of dissolution for Miscanthus in hydrophilic ionic liquids

► We investigate the solubility of a lignocellulosic biomass feedstock, in various ionic liquids. ► The dissolution of Miscanthus in ILs is influenced by temperature, water content and particle size. ► Strong hydrogen bonding acceptor anion of ILs is responsible for the dissolution of Miscanthus. ► We demonstrate the usefulness of COSMO-RS in understanding solvation of Miscanthus in ILs. Miscanthus is a potential feedstock for the production of biofuels. Lignocellulosic biomass is not soluble in conventional solvents, but Miscanthus and other lignocellulosic biomass have reasonable solubilities in some ionic liquids. The solubility of Miscanthus in a variety of hydrophilic ionic liquids was measured as a function of particle size, temperature and time for dissolution. In addition to temperature and time, the ionic liquid anion has a significant effect on solubility and rate of dissolution. The moisture content of Miscanthus lowers its solubility in certain ionic liquids. Chloride, acetate, and phosphate-based ionic liquids favor solubility. A tentative correlation for the solubility of Miscanthus is proposed in terms of Abraham solvation parameters obtained from quantum-chemical model COSMO-RS (Conductor like Screening Model-Real Solvents).