Combining near and mid infrared spectroscopy for heavy oil characterisation

• Published in: Fuel (Guildford) 2014-10, Vol.133, p.310-316
• Main Authors: Laxalde, Jérémy, Caillol, Noémie, Wahl, François, Ruckebusch, Cyril, Duponchel, Ludovic
• Format: Article
• Language: English
• Subjects: Applied sciences; Chemical Sciences; Chemometrics; Energy; Energy. Thermal use of fuels; Exact sciences and technology; Fuels; Heavy oil; Infrared spectroscopy; Multiblock method; or physical chemistry; SARA; Theoretical and
• ISSN: 0016-2361; 1873-7153
• DOI: 10.1016/j.fuel.2014.05.041

[Display omitted] •Highlighting of complementary information in NIR and MIR spectroscopy for the description of SARA contents in heavy oil.•First evaluation of NIR and MIR combination for heavy oil characterisation.•NIR spectroscopy found to be the most appropriate technique for the prediction of SARA contents.•Combination of NIR and MIR has resulted in a significant improvement of resin content prediction.•A possibility to have a spectral interpretation of multiblock models. In this study, the potential of combining NIR and MIR spectral range for the determination of Saturate, Aromatic, Resin and Asphaltene (SARA) contents in heavy oils was evaluated. The work aimed at better understanding the contribution of each spectral range and, at highlighting complementary information for the description of SARA contents. A further objective was to observe if more accurate models could be obtained combining the two spectral domains. For this purpose, two multiblock methods, MB-PLS and S-PLS, were chosen. In a first step, PLS models were developed for each spectral range and results were compared on the basis of a statistical test. No significant difference was found for the prediction of resins and asphaltenes. On the contrary, for the prediction of saturate and aromatic contents, NIR performed better. In a second step, MIR and NIR spectral range were combined using MB-PLS and S-PLS. A significant improvement was obtained for the prediction of resin content using MB-PLS. In addition, the contributions of CH out of plane bending vibrations and aromatic CC stretching vibrations for the description of highly unsaturated compounds could be highlighted in MIR.