Partial Least-Squares (PLS) Correlation between Refined Product Yields and Physicochemical Properties with the ¹H Nuclear Magnetic Resonance (NMR) Spectra of Colombian Crude Oils

Abstract

A method was developed, in which the integral areas of resonance signals in 12 regions of the 1H nuclear magnetic resonance (NMR) spectra of 5 widely different Colombian crudes and a crude mixture were correlated with selected physicochemical properties and standard distillation cut yields. The crudes used ranged from very light to heavy aromatics, thus covering a wide range of chemical compositions. The relationship between the NMR spectra and the properties of interest was obtained with the partial least-squares (PLS) algorithm. High correlation values were obtained for all of the PLS models used. The R2 values of the prediction models for the physicochemical properties and SimDis results were >0.95, while the CV-q2 values fluctuated between 0.74 and 0.99. The properties of an unknown crude or crude mixtures can be obtained from their 1H NMR spectra and the use of the PLS models developed in this work. The correlation method is very fast (1 h instead of several weeks) and much less costly than the conventional ones.