Comprehensive two-dimensional GC for the analysis of low-molecular-weight oxygenates in three different matrices from...

A method using comprehensive (2) DGC with flame ionisation detection was developed to quantify 17 low-molecular-weight oxygenates in three different matrices, namely water, oil and gas, using a single calibration. The method was required for the pilot-plant experiments of a chemical process unit. From an analytical perspective, the first task was to find a suitable analytical method with sufficient selectivity and sensitivity to analyse the selected oxygenates at low levels in the presence of high levels of hydrocarbons. The second was the accurate quantitation of oxygenates in the water, oil and gas fractions, using the same instrument and calibration. Both these requirements were met by using comprehensive (2) DGC in the inverse configuration and calibrating the detector with the number of moles injected versus response. The method was successfully applied for the characterisation of the reactor product stream of the chemical process unit and made it possible to determine the fate of the selected oxygenates after passing through the reactor. The development of the method and some of the results are described in this paper.