Deep-eutectic solvent based on ascorbic acid and preparation method and application of deep-eutectic solvent

The invention discloses a deep-eutectic solvent based on ascorbic acid and a preparation method and application of the deep-eutectic solvent. The deep-eutectic solvent is obtained by using choline chloride and the ascorbic acid (or erythorbic acid) as raw materials (wherein a stoichiometric ratio of choline chloride and the ascorbic acid is 1:1-2:1) and stirring for 0.5-12h while heating at 60-100 DEG C under conditions of protection by inert gas (like nitrogen, argon and carbon dioxide) or vacuumizing. In the preparation method, a deep-eutectic principle is utilized, and the ascorbic acid (or the erythorbic acid) which is unstable to heat or oxygen and choline chloride form intermolecular hydrogen bonding so as to prepare the liquid-state deep-eutectic solvent which is clear and transparent at room temperature. The preparation method has the advantages that preparation is simple, reagents are low in price and nontoxic, environment pollution is little, stability is high, and the deep-eutectic solvent is shall