title: Quantification of animal fat biodiesel in soybean biodiesel and B20 diesel blends using near infrared spectroscopy and synergy interval support vector regression.
abstract: In this work, multivariate calibration based on partial least squares (PLS) and support vector regression (SVR) using the whole spectrum and variable selection by synergy interval (siPLS and siSVR) were applied to NIR spectra for the determination of animal fat biodiesel content in soybean biodiesel and B20 diesel blends. For all models, prediction errors, bias test for systematic errors and permutation test for trends in the residuals were calculated. The siSVR produced significantly lower prediction errors compared to the full spectrum methods and siPLS, with a root mean squares error (RMSEP) of 0.18%(w/w) (concentration range: 0.00%-69.00%(w/w)) in the soybean biodiesel blend and 0.10%(w/w) in the B20 diesel (concentration range: 0.00%-13.80%(w/w)). Additionally, in the models for the determination of animal fat biodiesel in blends with soybean diesel, PLS and SVR showed evidence of systematic errors, and PLS/siPLS presented trends in residuals based on the permutation test. For the B20 diesel, PLS presented evidence of systematic errors, and siPLS presented trends in the residuals.
authors.affiliation: Institute of Chemistry, University of Campinas-UNICAMP, P.O. Box 6154, 13083-970 Campinas, SP, Brazil.
authors.forename: Paulo Roberto
authors.initials: PR
authors.lastname: Filgueiras
authors.affiliation: Institute of Chemistry, University of Campinas-UNICAMP, P.O. Box 6154, 13083-970 Campinas, SP, Brazil.
authors.forename: Júlio Cesar L
authors.initials: JC
authors.lastname: Alves
authors.affiliation: Institute of Chemistry, University of Campinas-UNICAMP, P.O. Box 6154, 13083-970 Campinas, SP, Brazil. Electronic address: ronei@iqm.unicamp.br.
authors.forename: Ronei Jesus
authors.initials: RJ
authors.lastname: Poppi
mesh_terms: D000818:Animals; D056804:Biofuels; D002138:Calibration; D005223:Fats; D008962:Models, Theoretical; D013025:Glycine max; D019265:Spectroscopy, Near-Infrared / Q000379:methods*; D060388:Support Vector Machine
chemical_list: D056804:Biofuels; D005223:Fats
keywords: Animal fat; Biodiesel; Partial least squares; Permutation test; Support vector regression