Study of correlations between composition and physicochemical properties during methylic and ethylic biodiesel synthesis

•Density and viscosity were determined for samples simulating process.•Correlations between physicochemical parameters and composition were established.•Wasted catalyst, alcohol and water amount has no major influence on the properties.•Properties are mainly influenced by the amount of FAAE, TAG, DAG and MAG.

In this work, correlations between the physicochemical parameters (density and kinematic viscosity) and the composition of various samples, obtained during the biodiesel production process of methylic and ethylic soybean biodiesel, were investigated. The results point out that the composition of the medium in terms of remaining catalyst and its residues, alcohol and water content, among others variables, has no significant influence on the physicochemical properties studied. These findings are mainly influenced by the composition of the medium in terms of FAAE, TAG, DAG and MAG.