An HPLC-ESI-QTOF method to analyze polar heteroatomic species in aviation turbine fuel via hydrophilic interaction chromatography through statistical analysis of mass spectral data

• HILIC-ESI-QTOF method analyzes polar heteroatomic species. • Method enables high-fidelity data for chemometric analysis. • Identified N-compounds linked to deposit formation via FC. • Three trends relate N-species to deposit formation identified. • DBE and carbon number linked to deposit formation. Aviation turbine fuel, a complex mixture of thousands of compounds, contains small amounts (<0.1% by mass) of oxygen (O), nitrogen (N), and sulfur (S)-containing species that significantly impact fuel properties. A new analytical method employing hydrophilic interaction liquid chromatography (HILIC) coupled with electrospray ionization and quadrupole time-of-flight mass spectrometry (ESI-QTOF) has been developed to identify these heteroatomic, polar compounds. HILIC offers advantages such as minimal sample preparation without extraction, preserving compounds of interest, and enabling high-fidelity data acquisition for chemometric analysis. This method, applied to a dataset of 89 aviation turbine fuels, allows for statistical analysis of the complex chemical composition, comprising thousands of individual compounds and numerous chemical classes. This approach facilitates a deeper understanding of fuel composition to optimize production and use. This effort developed a chemometric analysis workflow for linking identified polar compounds to key performance parameters, such as thermal oxidative stability. A fold change (FC) analysis of ESI-QTOF data identified nitrogen compounds associated with quartz crystal microbalance (QCM) autoxidative deposit formation. Three distinct trends emerged relating nitrogen compound classes and deposit formation: 1) increased deposit regardless of carbon number [double bond equivalence (DBE)>/=4], 2) decreased deposit at low carbon numbers and increased deposit at high carbon numbers (DBE = 1–3), and 3) increased deposit for specific compounds while others showed no change (DBE = 0). These findings provide valuable insights, confirming previous research, uncovering new information, and highlighting areas for future investigation.