The influence of column temperature on the extrapolated values of the retention factor in reversed-phase liquid chromatography for water as mobile phase

The dependences of the retention factor for some aromatic hydrocarbons at different column temperatures on the concentration of the organic modifier in mobile phase (acetonitrile) were studied under reversed-phase liquid chromatography, using two C18 chromatographic columns with the same constructive characteristics. From these dependences the extrapolated values of the retention factor for the aromatic hydrocarbons were
calculated and then they were used for studying their temperature dependence by means of the van’t Hoff plots. The graphs between the logarithm of the retention factor and the inverse value of absolute temperature of the column were characterized by good determination coefficients. The standard enthalpy variation associated to the transfer of studied hydrocarbons from the aqueous mobile phase to the stationary phase was calculated from these van’t Hoff plots.