Adoption of the Time Resolved Fluorescence to Oil Type Identification

The present development of a basic science, including physics of stimulated emission of light, opens up new diagnostic possibilities in relation to the quality of oils, including marine fuels and lubricants. In complicated chemical composition of oils both light absorbing compounds and compounds that emit light (fluorescent) are included. This causes the formation of complex structures in the spectral plots of fluorescence intensity as a function of wavelength of light exciting fluorescence and as a function of the wavelength of light emitted. Since the fluorescence excitation occurs in a short time of its disappearance. The shape of the fluorescence decay function depends on the chemical composition of oil, therefore, includes a mention of its kind, quality, level of degradation, and the like. In this paper exemplary charts of the intensity decay curves in different parts of the fluorescence spectra are shown (for light fuel). Presented charts are obtained using the experimental device constructed in Bremerhaven University of Applied Sciences (Germany) and are the attempt to use ability of oil substance to manifest its composition in the form of the fluorescence decay curve. An analysis of the chart shows that decay of fluorescence in this case is described by biexponential curve, therefore a kind of oil can be represented by two numerical values – two decay time constants. Operational use of this method will be possible only after a comparative study of different types and quality of oil in relation to the shape of the fluorescence decay curves.