Selective extraction of polyhydroxy compounds using hydrophobic ionic liquids

•An efficient selective extraction method of polyhydroxy compounds was established.•The purities of isosorbide and isomannide extracted were more than 99.60 wt% and 99.99 wt% respectively.•Polyhydroxy compounds dissolved in hydrophobic ionic liquids could be directly extracted by water without chemical modification.•Hydrophobic ionic liquids could be easily regenerated, with a minimum regeneration rate of 93.22% and a maximum of 97.04%.