Mapping of Trace Hydrocarbon Concentrations in Two-Dimensional Flames Using Single-Photon Photoionization Mass Spectrometry

• Published in: Analytical chemistry (Washington) Vol. 71; no. 2; pp. 364 - 372
• Main Authors: McEnally, Charles S, Pfefferle, Lisa D, Mohammed, Rahima K, Smooke, Mitchell D, Colket, Meredith B
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 15.01.1999
• Subjects: Analytical chemistry; Chemistry; Combustion. Flame; Exact sciences and technology; General and physical chemistry; Hydrocarbons; Scientific imaging; Spectrometric and optical methods; Trace analysis; Turbulent flame; Chemical analysis; Multicomponent analysis; Hydrocarbon; Photoionization; Combustion gas analysis; Mass spectrometry; Concentration distribution
• ISSN: 0003-2700; 1520-6882
• DOI: 10.1021/ac980818r

Single-photon photoionization mass spectrometry (SPPI-MS) with a vacuum ultraviolet laser beam at 118 nm has been used to quantify trace hydrocarbons sampled with a quartz microprobe from an axisymmetric nonpremixed methane/air jet flame. More than 20 C3−C12 hydrocarbons were detected, including linear species, single-ring aromatics, and two- or three-ring polynuclear aromatic hydrocarbons. For each of these species, high-resolution two-dimensional concentration maps were obtained that are suitable for comparison with detailed computer models of aromatic hydrocarbon formation and growth. Preliminary comparison with such a model indicates that the sampling process accurately captures the spatial structure of the flame. In general, the results show that the broad-band sensitivity, part-per-million detection limits, negligible ion fragmentation, and rapid data acquisition rate of SPPI-MS make it an ideal technique for studying the complex hydrocarbon chemistry that occurs in flames.