Biodieseis leves derivado dos óleos da macaúba e do palmiste: propriedades de misturas com o querosene na perspectiva de um combustível alternativo de aviação

Abstract

The continuous search for new renewable fuels, as a response to the growing global demand of energy but also and mostly to environmental issues, strongly stresses the importance of developing alternative aviation fuels, particularly those derived from biomass, as could be from distillated fractions of the conventional biodiesel, to be blended with or even to entirely replace the aircraft mineral kerosene. Oils from the macaúba (Acrocomia aculeate) and palm kernel (Elaeis guineensis) were individually transesterified with methanol through the classical reaction under homogeneous alkaline catalysis. The raw macaúba or palmiste fatty acid methyl esters (FAME) were then subjected to atmospheric distillation in order to obtain fractions enriched in short-chain esters, ranging from C8 to C14, to be blended with the conventional mineral jet fuel. In this study, blends of such light biodiesels were prepared with the Jet A-1 (as named by the ASTM, or QAV 1, according to the Brazilian ANP nomenclature) kerosene and characterized for their density, distillation fractions, thermal behavior (thermogravimetry and differential calorimetry analyses), freezing point, flash point, and calorific value. These analyses were carried out as criterions to determine the most suitable light biodiesel:kerosene ratio, basing on the values recommended by ANP for such assessed properties. The blends corresponding to 5; 10 and 20 vol% of enriched short-chain esters from macaúba or palm kernel in the bended fuel with Jet A-1 showed values well within the limits recommended by both ANP 37 and ASTM D1655.