Oxidation reactivity and nanostructural characterization of the soot coming from farnesane - A novel diesel fuel derived from sugar cane

Abstract

Thermogravimetric analysis (TGA), X-Ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy (RS) and High-resolution transmission electron microscopy (HRTEM) techniques were used to characterize soot gathered from a conventional automotive diesel engine fueled by ultra-low sulfur diesel, gas-to-liquid (GTL), biodiesel, and a diesel fuel derived from sugar cane named farnesane. Soot oxidation reactivity, volatile organic fraction, and active surface area (determined with TGA) followed the order: biodiesel >> GTL > farnesane ≅ diesel. Among all soot samples, biodiesel exhibited the highest FTIR absorption peaks for oxygenated and aliphatic functional groups. The degree of disorder of graphene layers (RS analysis bands), fringe interspace distance (∼1.5 nm with XRD, and ∼0.46 nm with HRTEM), fringe length (∼2.5–4 nm with XRD, and ∼0.9 nm with HRTEM), median fringe tortuosity (∼1.1), mean primary particles diameter (∼25 nm), and fractal dimension (∼2.3) were similar for all soot samples. HRTEM images revealed a marked difference in the burning pattern for biodiesel soot in comparison with the other soot samples. Given the results of this work, under the specific engine test condition and engine configuration, farnesane fuel seems so far to be a promising renewable paraffinic fuel for current diesel engines.