H. Snijders et al., OPTIMIZATION OF TEMPERATURE-PROGRAMMED GAS-CHROMATOGRAPHIC SEPARATIONS .1. PREDICTION OF RETENTION TIMES AND PEAK WIDTHS FROM RETENTION INDEXES, Journal of chromatography, 718(2), 1995, pp. 339-355
Citations number
32
Categorie Soggetti
Chemistry Analytical","Biochemical Research Methods
A numerical method is described to predict retention times and peak wi
dths of a mixture containing components with known identities in capil
lary gas chromatography. The procedure is based on extracting thermody
namic values (enthalpy and entropy terms) from Kovats retention indice
s. Next, a numerical procedure is developed that uses these data to ca
lculate retention times and peak widths on any capillary column contai
ning the same stationary phase but with a different phase ratio. The e
stimations are based on a sound theoretical basis. The predictions can
be performed either in the isothermal or temperature-programmed (sing
le- or multi-ramp) mode. In the temperature programs, which cover a br
oad temperature range, isothermal plateaus are allowed. Errors in the
predictions of retention times are generally less than 4%. Prediction
of peak widths under the same conditions can be performed with errors
of about 10%. An attractive feature of the approach is, that once the
thermodynamic values of the solutes of interest are known, future opti
mizations can be performed without the need to perform experimental in
put runs. This indicates that the concept can be used for complete off
-line simulations and/or optimizations of gas chromatographic separati
ons.