A method of bulk liquid membrane (BLM) using complex of di(2-ethylhexyl) phosphoric acid (D2EHPA) and O,O'-dibenzoyl-(2R, 3R)-tartaric acid (L-(-)-DBTA) was developed for the extractive resolution of racemic mandelic acid (rac MA). The effects of resolution time, concentration of D2EHPA in the organic phase, concentration of rac MA in the feed phase, stirring speed and temperature on extractive resolution were studied. The experimental results have shown that the greatest separation factor (α) 2.74 and the enantiomeric excess value (ee, %) 46.47% were obtained when the resolution time was about 4 h, the molar concentration ratio of rac MA, D2EHPA and L-(-)-DBTA 0.05:0.2:0.3, the stirring speed 400 r min-1 and the temperature 35 ºC. The developed method is helpful for optimizing the transport of BLM systems and for large-scale production of pure enantiomer.
D2EHPA; L-(-)-DBTA; bulk liquid membrane; extraction resolution; mandelic acid
