Rapid determination of thermodynamic parameters from one-dimensional programmed-temperature gas chromatography for use in retention time prediction in comprehensive multidimensional chromatography

A new method for estimating the thermodynamic parameters of Delta H(T-0), Delta S(T-0), and Delta C-p for use in thermodynamic modeling of GCxGC separations has been developed. The method is an alternative to the traditional isothermal separations required to fit a three-parameter thermodynamic model to retention data. Herein, a non-linear optimization technique is used to estimate the parameters from a series of temperature-programmed separations using the Nelder-Mead simplex algorithm. With this method, the time required to obtain estimates of thermodynamic parameters a series of analytes is significantly reduced. This new method allows for precise predictions of retention time with the average error being only 0.2 s for 1D separations. Predictions for GC x GC separations were also in agreement with experimental measurements; having an average relative error of 0.37% for (1)t(r) and 2.1% for (2)t(r). (C) 2013 Elsevier B.V. All rights reserved.