Mapping and quantifying isomer sets of hydrocarbons (≥C12) in diesel exhaust, lubricating oil and diesel fuel samples using GC× GC-ToF-MS
Research output: Contribution to journal › Article
Authors
Colleges, School and Institutes
External organisations
- Department of Mechanical Engineering
- Beihang University
- King Abdulaziz University, Department of Environmental Sciences, Center of Excellence in Environmental Studies, Jeddah 21589, Saudi Arabia
Abstract
Airborne particles and vapours, like many other environmental samples including water, soils and sediments, contain complex mixtures of hydrocarbons, often deriving from crude oil either before or after fractionation into fuels, lubricants and feedstocks. Comprehensive 2D gas chromatography time-of-flight mass spectrometry (GC×GC-ToF-MS), offers a very powerful technique that separates and identifies many compounds in complicated hydrocarbon mixtures. However, quantification and identification of individual constituents at high ionization energies would require hundreds of expensive (when available) standards for calibration. Although the precise chemical structure of hydrocarbons does matter for their environmental impact and fate, strong similarities can be expected for compounds having very similar chemical structures and carbon numbers. There is, therefore, a clear benefit in an analytical technique which is specific enough to separate different classes of compounds and to distinguish homologous series while avoiding the need to handle each isomer individually. Varying EI (electron impact) ionization mass spectrometry significantly enhances the identification of individual isomers and homologous compound groups, which we refer to as <q>isomer sets</q>. Advances are reported in mapping and quantifying isomer sets of hydrocarbons (≥ C12) in diesel fuel, lubricating oil and diesel exhaust emissions. By using this analysis we report mass closures of ca. 90 and 75% for diesel fuel and lubricating oil, and identify 85 and 75% of the total ion current for gas- and particulate-phase diesel exhaust emissions.
Details
Original language | English |
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Pages (from-to) | 3047-3058 |
Number of pages | 12 |
Journal | Atmospheric Measurement Techniques |
Volume | 11 |
Issue number | 5 |
Publication status | Published - 29 May 2018 |