Automated Analysis of Petroleum- and Plastic-Derived Fuels by Gas Chromatography Coupled with Field Ionization Mass Spectrometry

Gas chromatography combined with field ionization mass spectrometry (GC × FIMS) was introduced more than 20 years ago. Despite the field ionization method’s unique capability to produce mostly molecular ions, it remained a niche technique. In this work, we present a renewed look at the comprehensive two-dimensional separation combining gas chromatographic retention and time-of-flight mass separation of the molecular ions generated by field ionization. Automated data processing, including noise removal, peak picking, and differentiation of nearly isobaric hydrocarbon and sulfur species, has been developed. Repeatability and robustness of GC × FIMS identifications are discussed as well as limitations with quantification. To evaluate the method performance, the resulting speciation of petroleum-derived samples using GC × FIMS is compared to measurements performed using comprehensive two-dimensional gas chromatography (GC × GC) and Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). Then, the GC × FIMS method is demonstrated on a variety of samples representing the petroleum hydrocarbon value chain. With a constant method and automated processing parameters, the detailed compositional characterization is obtained for (i) a wide range of petroleum fractions from naphtha to vacuum gas oil, (ii) refinery intermediates, such as light cycle oil and an aromatic bottom stream, (iii) commercial fuel, and (iv) plastic-waste-derived pyrolysis oil. Due to automated data processing, a comprehensive compositional analysis is available within 80 min, regardless of the sample type. Thereby, the presented method can be highlighted as a valuable tool for the swift and detailed characterization of diverse hydrocarbon mixtures.