Aplicação de Chalconas e Análogos com Aditivos Antioxidantes em Misturas de Diesel e Biodiesel

Abstract

The fossil fuels are precursors of a large share of pollutants gas emissions into atmosphere. Thus, there is a growing demand for renewable and less polluting energy sources. The biodiesel represents a promising alternative for Brazilian and global energy matrices diversification as well as for reducing the environmental impacts of internal combustion engines. However, the biodiesel using can generate some technical problems associated with its lower stability and greater susceptibility to degradation in relation to petroleum diesel. As an alternative to the aforementioned problems, additives improve the physicochemical properties maintenance for biodiesel and its blends with mineral diesel, during storage and transport operations. This work includes the structural, energetic and reactional analysis associated to a chalcone molecule that presented a potential application as additive for diesel/biodiesel blends. Stability tests of S10 B20 diesel blended with C18H18O4 chalcone, during storage for 140 days, indicated an increase of up 50% in the accelerated oxidation stability time by modified Rancimat test method in relation to lower concentrations of same compound, according to data extracted from literature. The GAP, calculated from HOMO and LUMO energy also indicate high reactional stability for C18H18O4, confirming its antioxidant potential and being in accordance with some information for other antioxidant compounds, recommended like fuel and oils antioxidant additives. The results also indicated antibacterial activity associated to C18H18O4 chalcone.