Prediction of retention indices of thiols and sulfides under different conditions of capillary gas chromatography.

Abstract

A method has been proposed to predict the retention indices(RI) of the title compounds under various separation conditions. When the presence of thiols or sulfides was confirmed by the subtraction or the shift of peaks, respectively, by means of the tandem combination of a post column reactor coated with silver nitrate and a flame photometric detector, a certain thiol or sulfide was chosen as the standard compound. The retention characteristics of the stationary phase for the particular type of compound were estimated from the RI of the standard. The RI of these types of compound could be predicted accurately by using the observed RI value of the standard and the RI values of the compound of interest on the couple of the stationary phases (polyethylene glycol 20M at 80°C and silicone oil DC-550 at 70°C). The contribution of the increments due to the atomic groups was added in calculation of the latter RI values.