Vibrational Spectroscopy for the Quantification of Hydrotreated Vegetable Oil (HVO) Advanced Biofuels in Petroleum-Derived Fuel Blends: A Minireview

Hydrotreated vegetable oil (HVO), also called hydrotreated esters and fatty acids (HEFA), is an advanced biofuel composed of a mixture of hydrocarbons, similar to petroleum-derived diesel oil and kerosene jet fuel. Due to this chemical similarity, the quantification of this type of biofuel in mixtures with petroleum-derived fuels is a challenging analytical task, whose solution requires carefully developed methods for practical applications. In this review are discussed analytical methods based on vibrational spectroscopy (near infrared and mid infrared absorption as well as Raman scattering) found in the literature, highlighting their advantages in relation to radiocarbon-based reference methods described in ASTM D6866-18, such as the possibility of discrimination and quantification of two different biofuels in mixtures with petroleum-derived fuels. In addition, these approaches are simpler, faster, and less expensive. Vibrational spectroscopy methods provide good accuracy and RMSEP values below 0.8% for quantification of HVO or HEFA in fuel mixtures.