An empirical equation for the calculation of retention time with extrapolation of temperature in gas chromatography

An empirical equation is proposed to accurately correlate isothermal data o ver a wide range of temperature With the equation ln k = A* + B*/T-lambda t he retention times of different solutes tested on OV-101, SE-54 and PEG 20M capillary columns have been achieved even when lambda is assigned a consta nt value of 1.7 Comparison with ln k = A + B/T and in k = c + d/T+ h/T-2, s hows that the proposed equation is of higher accuracy and is applicable to extrapolation calculation, especially from data at high temperature to thos e at low temperature. Parameters A* and B* as well as A and B are also disc ussed. The linear correlation of A* and B* is weaker than that of A and B.