A Comprehensive Characterization of Particulate Matter, Trace Elements, and Gaseous Emissions of Piston-Engine...

The gaseous and PM₁₀ emissions of a piston-engine aircraft during ground operations at different engine states (six engine speed points and three air/fuel mixtures) representing certain flight phases were concurrently measured from the exhaust duct. PM₁₀ emissions were sampled on a 47 mm-diameter polytetrafluoroethylene (PTFE) filter in order to be analyzed with an inductively coupled plasma mass spectrometry (ICP-MS/MS) to identify the presence and level of forty-eight elements. The most abundant element is found to be Pb (med = 4.6 × 10⁶ ng m^-3), which is 40 times the second most abundant element, Na (med = 1.1 × 10⁵ ng m^-3). The filters used for sampling exhaust gases tend to lighten with an increase in engine speed and leaning of the fuel mixture. The average of measured PM mass concentrations at all engine speeds were calculated to be 27.7 mg m^-3 (full-rich) > 26.7 mg m^-3 (best-power) > 24.7 mg m^-3 (best-economy). The total mass of the trace elements constitutes an average of 24.1 ± 12.8% of the mass of PM. Electron microscope analyses suggest that the particles enriched by Al tend to agglomerate in a needle-shaped structure.