Fluorescence analysis of crude oil samples with different spectral approaches

Fluorescence techniques based on emission spectrum, synchronous fluorescence spectrum(SFS), or three-dimensional (3D) fluorescence spectrum, have been widely used in medical, biological and chemical analyses. In the present paper, 25 crude oil samples from 15 different borefields in the concentration range from 10^-4 g · L^-1 to 10 g · L^-1 have been investigated with different spectral approaches. It was shown that, compared with conventional emission spectrum based technique used in oil logging, the 3D fluorescence technique can provide much more information in the analysis of crude oil samples but at the price of time consuming. While the SFS spectrum of a crude oil sample, taken under the emission and excitation wavelength synchronous scan with Δλ = 40 nm, can represent the main characteristic of the 3D spectrum provided, with even better spectral qualities. All the results suggest that SFS technique is a more suitable approach in crude oil sample analysis than the other two, and has a great potential to be developed as a new quantitative analysis method in petroleum logging.