Reconcentrating the Ionic Liquid EMIM-HSO Using Direct Contact Membrane Distillation.

Adequate water supplies are crucial for missions to the Moon, since water is essential for astronauts' health. Ionic liquids (ILs) have been investigated for processing metal oxides, the main components of lunar regolith, to separate oxygen and metals. The IL must be diluted in the process.

Deep eutectic solvents' ability to solubilize lignin, cellulose, and hemicellulose; thermal stability; and density.

An environmentally-friendly method to separate cellulose and hemicelluloses from lignin in recalcitrant biomass for subsequent conversion is desirable to reduce greenhouse gas generation. Easily-prepared, deep eutectic solvents (DESs) have low volatility, wide liquid range, non-flammability, nontoxicity, biocompatibility, and biodegradability. This study shows the DESs (formic acid:choline chloride, lactic acid:choline chloride, acetic acid:choline chloride, lactic acid:betaine, and lactic acid:proline) to be capable of preferentially dissolving lignin at 60°C.