Extension of the DSC method to measuring vapor pressures of narrow boiling range oil cuts

An application of the standard test method for determining vapor pressure of pure compounds by thermal analyses (ASTM E 1782) was extended to vapor pressure measurements of narrow boiling range oil cuts by differential scanning calorimetry (DSC). The reliability of this application was examined by measuring comparable vapor pressure curves of selected narrow boiling oil cuts via a DSC based method and a static method. The oil cuts were distilled from a gasoline fraction (boiling range from about 363 to 453 K) from oil shale retorting oil, which was produced from Estonian kukersite oil shale by the Galoter process. The representative DSC measurements presented cover the temperature range from 318 to 484 K and pressure range from 15 to 750 kPa. Based on the results of the study, the DSC based method (ASTM E 1782) can be suggested as an alternative approach for determining vapor pressures of narrow boiling range oil cuts, with advantages such as a small sample size, use of commercial equipment and no need for sample degassing.