Abstract
A gas-liquid chromatographic study of the interaction and elution characteristics of 47 paraffinic compounds from C
5
-C
14
normal, branched, and cyclic alkanes using 100% dimethyl polysiloxane and 35% diphenyl, 65% dimethyl polysiloxane as stationary phases is reported. It is shown that polysiloxane stationary phase in capillary column gas chromatography possesses excellent chromatographic properties and is unique in the separation of iso-paraffins. The mechanism, retention, and selectivity are discussed by measuring various thermodynamic parameters: the enthalpy of solution Δ H, the entropy of solution Δ S, and the free energy Δ G.