Otimização da síntese de biodiesel a partir do óleo das vísceras de Tilápia do Nilo

Abstract

Biofuels are alternative sources adopted by many countries in the world in order to reduce dependence on fossil fuels from hydrocarbons and hence assist in the conservation of the environment. In this context, biodiesel from various matrices derived from biomass, whether of plant or animal origin, stands out. Among these matrices, the oil of the Nile Tilapia viscera is highlighted here in Ceará because of the large potential of the state for growing this crop. Aiming means for optimizing the biodiesel production process, an experimental design becomes a very fast and convenient way to study the independent variables (temperature, reaction time and molar ratio) that have the strongest effect on the dependent variable (conversion methyl esters) was analyzed. We used the central composite design (CCD) of 2³ with 3 repetitions at the central point and 6 axial points totaling 17 experiments. Through linear regression model generated according to the experimental design done, the optimal conditions came up: 46,6ºC temperature, 60 minutes reaction time and molar ratio (alcohol:oil) 6:1, with maximum yield of 93.2 %. Therewith, the biodiesel was produced with the optimal conditions for the reaction of alkaline transesterification via methyl route, and characterized as the adequacy suggested by the National Petroleum Agency, Natural Gas and Biofuels, ANP Resolution No. 45 of 08.25.2014 and Resolution No. 51 of 25.11.2015. Thus, nearly all parameters were within the conforming, except for oxidation stability which requires the use of antioxidants in the composition for future marketing.