Selection of the most beneficial raw materials for the synthesis of biodiesel from a standpoint of its yield and physicochemical properties

Abstract

Biodiesel presents itself as one of the most promising alternative energy sources at the present time, both as a pure fuel and a mixed component of petroleum-based diesel fuels. According to research works carried out around the world, the addition of biodiesel to diesel oil is established to significantly improve the environmental friendliness of this oil product. Nevertheless, its effect on most regulated operational indicators remains ambiguous due to the characteristics of biodiesel fuel varying greatly depending on the feed-stock. The present paper is aimed at resolving the issue of selecting the most beneficial raw material for the synthesis of biodiesel from the perspective of the target product yield, physicochemical and low temperature characteristics. In this study, biodiesel was synthesised from five different edible vegetable oils (sunflower, mustard, linseed, corn and camelina) using ethanol and potassium hydroxide as transesterifying agent and catalyst, respectively. The main physicochemical (density, dynamic and kinematic viscosity, molecular weight) and low-temperature (cloud point and pour point) properties of vegetable oils, as well as biodiesel fuels derived therefrom, are determined. According to the obtained yield values of the target product, sunflower oil is shown to be the optimal raw material for the synthesis of biodiesel. From the position of their physical and chemical properties, sunflower and corn oil appear to equally preferential, while, with regard to low temperature properties, mustard oil turns out to be the optimal feedstock. Sunflower oil was additionally determined to be a leader in terms of economics. The paper presents recommendations for choosing the most preferable raw materials for the synthesis of biodiesel, which are useful in application of biodiesel as a mixed component for commercial diesel fuels.