Monitoring of Soybean Oil Transesterification by Spectrofluorimetry and Multivariate Calibration

Erika Maria de Oliveira Ribeiro^1*, Cristina Maria Quintella¹, Marilena Meira², Saionara Luna¹, Alexandre Kamei Guimarães¹, Weidson Leal Silva¹

¹Instituto de Química, Universidade Federal da Bahia, Campus de Ondina, Salvador, Brasil.
²Instituto de Educação, Ciência e Tecnologia da Bahia, Campus de Simões Filho, Brasil.

DOI: 10.4236/oalib.1100598                

Abstract

An analytical procedure was developed to monitor the transesterification of soybean oil using spectrofluorimetry and Partial Least Squares (PLS) regression. Excitation-Emission Matrix (EEM) fluorescence spectroscopy derived from 12 standard mixtures of triolein and ethyl oleate were used in the construction of a PLS model using the fluorescent spectra as independent variables and the values of the methyl oleate % (w/w) as dependent variables. The model presented a high correlation (0.99178) between values determined by the reference method (ATR-FTIR) and values predicted by the proposed method. The coefficient of determination (R²) for the curve was close to a value of 1 (0.9836), which indicated the strength in the association between the observed data for the two variables and the efficiency of the model to perform the analysis. Therefore, the association between spectrofluorimetry and PLS was shown to be a fast and accurate method for monitoring soybean oil transesterification.

Keywords

Soybean Oil, Transesterification, Spectrofluorimetry, PLS

Conflicts of Interest

The authors declare no conflicts of interest.

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