Temperature dependence of solvation heat capacities by gas chromatography Original Research Article

The temperature dependence of molar solvation heat capacity has been determined in the temperature range of 30–160 °C for C6–C10 n-alkanes and McReynolds test compounds on 100% poly(dimethylsiloxane) (PDMS) FSOT columns using the equations involving the temperature dependence of solvation enthalpy and entropy. The evaluation method is based on a rigorous statistical evaluation of the parameter estimations. On PDMS, column solvation heat capacity versus temperature curves are S-shaped for n-alkanes and for 1-butanol, while the temperature dependence of the other test compounds is more complicated. The results show near monotonous decrease of solvation heat capacity in the whole temperature range. Harmonic oscillator—rigid rotor assumption rationalizes the curves in a simplified way.