Abstract: Rapid and accurate determination of fatty acid methyl ester (FAME) content in marine fuel oil is of great significance for quality control of marine fuel. This article uses mid infrared spectroscopy analysis technology combined with chemometric methods to quantitatively analyze the FAME content in marine fuel oil. Based on the correlation between FAMEinfrared characteristic peak intensity and volume fraction, a partial least squares analysis model was used to establish an analysis model, which had good accuracy and stability. The regression coefficients of the models based on spectra collected by two different types of instruments are both greater than 0.99, with cross validation standard deviations of 0.2644 and 0.1517, and sample repeatability standard deviations of 0.08% and 0.17%, respectively. The results indicate that mid infrared spectroscopy can quickly and accurately detect the FAME content in marine fuel oil, providing a practical analytical tool for quality monitoring of marine fuel oil.

Key words: mid infrared spectroscopy, chemometrics, partial least squares, marine fuel oil, fatty acid methyl ester