Comparison of the behaviour of gas-liquid and gas-liquid-solid capillary columns through the determination of thermodynamic characteristics

Interpolation methods, used for the prediction of retention times in programmed temperature capillary gas chromatography, employ equations whose parameters are correlated, through the capacity factor and the phase ratio of the column, with the thermodynamic parameters, that can be calculated by using retention data obtained at various temperatures. Homologous series of organic compounds (linear alkanes and alcohols) were analysed on bonded phase polar, non-polar and carbon layer open tubular columns and the values of some thermodynamic parameters were obtained. Their dependence on the polarity of the liquid phase and of the solutes, film thickness, temperature of the column, was investigated and allowed comparison of the behaviour of the different phases tested.