Characterization of Organic Nitrogen Compounds and Their Impact on the Stability of Marginally Stable Diesel Fuels

Abstract

A set of low sulfur diesel fuels from the Western Pacific region were found to be unstable during storage although they passed all standard specification tests. This sample set was found to have high nitrogen content. Initially, liquid-liquid extractions with a mild aqueous acid were performed to separate basic and non-basic nitrogen groups in an attempt to determine if these organonitrogen classes were responsible for the poor stability. The findings of this study indicate that there may be a correlation between the acid-extractable nitrogen compounds in these fuels and the formation of high levels of particulates in storage. In order to develop a more comprehensive understanding of the classes and distributions of organonitrogen compounds in fuels, a novel analytical method was developed using two-dimensional gas chromatography with nitrogen chemiluminescence detection (GCxGC-NCD). The GCxGC-NCD analyses revealed the presence of three distinct groups of nitrogen compounds. One group corresponded to the ...