63 APPLICATION OF FLUORESCENCE SPECTROSCOPY FOR SPECTRAL DISCRIMINATION OF CRUDE OIL SAMPLES

Abstract. Spectroscopic techniques have been extensively used in the petroleum industry for the characterization of crude oils. The present article shows the results of the application of fluorescence techniques for the analysis of the density of Brazilian crude oil samples. Fluorescence emission spectra of crude oil consist of relatively broad bands in the visible region (from ca. 350 to 650 nm), the intensities of which tend to accompany the API grade. Synchronous Fluorescence Spectroscopy (SFS) was performed with a wavelength interval of 50 nm starting the excitation at 450 nm. Time-Resolved Fluorescence Spectroscopy (TRFS) showed that the fluorescence lifetime is related to the API value, lighter oils with higher API exhibiting a longer lifetime. The present results demonstrate that fluorescence spectroscopy is useful in the characterization of complex samples like crude petroleum