Retention Mechanism of Phenolic Compounds in Subcritical Water Chromatography

The transfer enthalpies and entropies of hydroxyl and nitryl in different mobile phase systems were compared by van＇t Hoff curve. Results suggest that the presence of acetonitrile and methanol in the mobile phase may decrease the interaction of solute and stationary phase with respect to subcritical water, thereby reducing the contribution of enthalpy to the retention. Retention mechanisms of phenolic compound appear to be more similar in subcritical water and water/methanol systems on the PRP-1 column. Hydrogen bond in subcritical water system plays a very important role in the retention of the phenols.