Characterization of gasoline/ethanol blends by infrared and excess infrared spectroscopy

FUEL

卷:141

Article

Corsetti, Stella^1,2  Zehentbauer, Florian M.^1,3  McGloin, David²  Kiefer, Johannes^1,3,4 

[1] Univ Aberdeen, Sch Engn, Aberdeen AB24 3UE, Scotland

[2] Univ Dundee, SUPA, Sch Engn, Div Phys, Dundee DD1 4HN, Scotland

[3] Univ Bremen, D-28359 Bremen, Germany

[4] Univ Erlangen Nurnberg, Erlangen Grad Sch Adv Opt Technol SAOT, D-91054 Erlangen, Germany

关键词: Biofuel;    Fossil fuel;    Alcohol;    Excess absorption;    Frequency shift;   

DOI  :  10.1016/j.fuel.2014.10.025

来源: Elsevier

【 摘 要 】

Fuels for automotive propulsion are frequently blends of conventional gasoline and ethanol. However, the effects of adding an alcohol to a petrochemical fuel are yet to be fully understood. We report Fourier-transform infrared spectroscopy (FTIR) of ethanol/gasoline mixtures with systematically varied composition. Frequency shifts and excess infrared absorbance are analyzed in order to investigate the mixture behavior at the molecular level. The spectroscopic data suggest that the hydrogen bonding between ethanol molecules is weakened upon gasoline addition, but the hydrogen bonds do not disappear. This can be explained by a formation of small ethanol clusters that interact via Van der Waals forces with the surrounding gasoline molecules. Furthermore, approaches for measuring the chemical composition of ethanol/gasoline blends by FTIR are discussed. For a simplistic approach based on the Beer-Lambert relation, an optimized set of parameters for quantitative measurements are determined. The best compromise between measurement sensitivity and accuracy is found for the CO stretching mode of the alcohol. For the traditional method of calibrating the ratio of integrated band intensities of the CH and OH stretching regions it is found that narrowing the spectral window of the CH stretch can significantly improve the measurement sensitivity. (C) 2014 Elsevier Ltd. All rights reserved.

【 授权许可】

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