Abstract: Molecular spectroscopy technology such as infrared (IR) and near infrared (NIR) spectroscopy is widely used in rapid assay for crude oil, while Raman spectroscopy is hardly used due to the badly fluorescence effect of crude oil. To evaluate the feasibility of crude oil rapid assay by Raman spectroscopy, Raman, IR and NIR spectroscopy combined with chemometrics were used to analyze the density, carbon residue value and wax content of crude oil. The spectral repeatability and analysis precision were evaluated. Results show that the spectral repeatability and analysis precision of Raman spectroscopy are worse compared with IR and NIR, demonstrating that Raman spectroscopy is not suitable for crude oil rapid assay.

Key words: Raman spectroscopy, infrared spectroscopy, partial least squares, crude oil assay