Application of Vibrational Spectroscopy to the Determination of Viscosity and Aniline Value of Hexanol Blended Diesel

Abstract

Presently there is a great interest in the development of green fuels capable of producing reduced emissions. The two parameters, among many others, that determine the efficiency of the fuel are the viscosity and aniline point of the fuel. The authors present a vibrational spectroscopy-based analytical method for the estimation of viscosity and aniline value of the 5-45% hexanol blended diesel. The infrared (IR) and near infrared (NIR) spectra of the blended diesel were recorded in the range of 4000-700 cm-1 and 9000-5000 cm-1. The major peaks in both spectra were assigned to the fundamental and overtone vibrations of the CH and OH functional groups. The PLS (partial least square) analysis of the spectra showed that both IR and NIR spectra can be successfully used as alternative tools for the determination of the viscosity and aniline value of the hexanol blended diesel fuel. The high correlation coefficients (R2) for the viscosity and aniline values in the IR (0.994, 0.996) and NIR (0.995, 0.996) indicated the success of the procedure.