Analysis by x-ray photoelectron spectroscopy/depth profiling of thin, gasoline-derived deposit films

Journal Article · Sat Sep 01 04:00:00 EDT 1990 · Industrial and Engineering Chemistry Research; (USA)

DOI:https://doi.org/10.1021/ie00105a030· OSTI ID:6202641

Tseregounis, S I ^[1]

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1. Fuels and Lubricants Dept., General Motors Research Laboratories, Warren, MI (US)

Fuel-derived deposits on injectors and elsewhere in engines can severely impair engine performance. This paper reports on a laboratory test procedure developed to produce thin deposit films from oxidized fuel on steel. The deposit films were analyzed by using x-ray photoelectron spectroscopy (XPS or ESCA) and depth profiling. The deposits were carbonaceous with lesser amounts of oxygen, sulfur, and nitrogen. The total sulfur concentration in the deposits was 5--10 times higher than the concentration of sulfur in the original gasoline. Ion bombardment preferentially removed oxygen from the deposit layer, revealing that sulfur in the deposits was in the form of oxygenated compounds (RSO{sub 2}R, RSO{sub 2}OR, ROSO{sub 2}OR, RSO{sub 2}OSO{sub 2}R) and removal of oxygen converted them to lesser or non-oxygen-containing compounds (RSR, RSOR, RSSR, RSSO{sub 2}R). Fuel samples were spiked with two sulfur-containing chemicals, thionanisole and thianaphthene. Neither compound participated directly in the deposit formation process. Thinner deposit films were formed on polished and oxidized surfaces rather than on polished-only surfaces.

• OSTI ID: 6202641
• Journal Information: Industrial and Engineering Chemistry Research; (USA), Journal Name: Industrial and Engineering Chemistry Research; (USA) Vol. 29:9; ISSN 0888-5885; ISSN IECRE
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
023000 -- Petroleum-- Properties & Composition
33 ADVANCED PROPULSION SYSTEMS
330101* -- Internal Combustion Engines-- Spark-Ignition
36 MATERIALS SCIENCE
360105 -- Metals & Alloys-- Corrosion & Erosion
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400101 -- Activation
Nuclear Reaction
Radiometric & Radiochemical Procedures
CARBON
CHEMICAL COMPOSITION
CORROSIVE EFFECTS
DEPOSITS
ELEMENTS
ENGINES
FILMS
FUEL INJECTION SYSTEMS
FUEL SYSTEMS
FUELS
GASOLINE
HEAT ENGINES
INTERNAL COMBUSTION ENGINES
LIQUID FUELS
NITROGEN
NONMETALS
OXYGEN
PETROLEUM PRODUCTS
SPECTRA
SULFUR
SURFACES
THIN FILMS
X-RAY SPECTRA