文摘
A selective separation of vitamin D<sub>3sub> and tachysterol<sub>3sub> by solvent extraction with 7 organic solvents and 11 ionic liquids (ILs) has been reported. Among organic solvents sulfolane showed optimal extraction performance, giving only a selectivity of 1.44 for tachysterol<sub>3sub> over vitamin D<sub>3sub>. ILs with unsaturated bonds demonstrated high selectivity probably due to their different 蟺鈥撓€ interactions with the two compounds. A pyrrolidinium-based ionic liquid, for example, [BMPr][NTf<sub>2sub>], provided the highest selectivity up to 1.77. Acceptable selectivity and distribution coefficients were observed by a combination of organic solvents and ILs as extracting agents. In this work, the effects of concentrations, anions, cations, and substituent of ILs were investigated, which may provide a rational strategy for the design of novel ILs for extractive separation of structural analogues. The purification and recovery of vitamin D<sub>3sub> via continuous multistage extractions were simulated, indicating that IL-based liquid鈥搇iquid extraction might be superior to traditional organic solvents in practical production.
Keywords:
vitamin D<sub>3sub>; tachysterol<sub>3sub>; liquid鈭抣iquid extraction; organic solvents; ionic liquids; continuous multistage extraction