Three chloro-substituted and threebromo-substituted styrene oxides were separated by gas chromatography using thechiral capillary column of Chiraldex G-PN. According to the results, the enantiomer with lower capacity factor (k′) showed larger separation factor (α′) and better resolution. It suggests that the interaction between sample andimmobile phase (include dilutent) contains chiral and achiral parts: chiral separation results from chiral interaction, and achiral interaction affects retention behavior of samples. The method has been used for determining the ee value of optically active styrene oxides.

Key words: capillary gas chromatography, chiral separation, cyclodextrin chiral selector, chloro-substituted styrene oxide, bromo-substituted styrene oxide