ABSTRACT

Field Ionization Mass Spectrometry (FIMS) has been used to characterize fossil fuels. Detailed analysis of a range of fossil fuels by FIMS has been well established at SRI through support of numerous agencies, including the Naval Research Laboratory on the analysis of middle distillates by high-resolution FIMS and on the chemistry of storage stability of diesel fuels. Gas chromatography and FIMS complement each other in their ability to separate compounds. One convenient way to display the composition of a hydrocarbon fuel is by using a z-series table. To extract a z-series table from the total ion chromatograms involves five steps. Alkyl dibenzothiophenes are among the most difficult set of compounds to hydrodesulfurize. With increasing demand for fuels with extremely low sulfur content, it is necessary to desulfurize dibenzothiophenes as well. Alkylindoles are a key component of the sediments formed during long-term storage of diesel fuels.