Publication

Abstract : Extracting useful materials from the effluents help in cost reduction of catalyst synthesis for transesterification reaction. Hence, in this study, CaO-SiO2 and MgO–SiO2 catalysts were prepared in which the nano–silica was extracted from the steel slag. The properties of the slag, extracted nano-silica and synthesized catalysts were characterized in detail. Biodiesel was synthesized from Euglena sanguinea. Optimization of various parameters of transesterification process was done by RSM using CCD. The presence of biodiesel was confirmed with the help of 1H-NMR, GC–MS and FTIR spectroscopy. The synthesized MgO–SiO2 and CaO–SiO2 catalyst possessed a surface area of 31 and 15 m2/g respectively. The optimized parameters obtained using CaO–SiO2 were methanol to oil ratio of 9:1, catalyst weight % of 5 and duration of 3 h. The optimized parameters of the MgO–SiO2 catalyst were–methanol to oil ratio of 9:1, catalyst weight % of 6 and reaction time of 5.5 h. The biodiesel yield obtained by using CaO–SiO2 and MgO–SiO2 corresponds to 87 and 83. 5% respectively. The loss of yield after reusing 5 times was 20 and 10% for CaO–SiO2 and MgO–SiO2 respectively. Kinetic models were compared with respect to their fit with experimental data. Pseudo–first order kinetics was a better fit for the experimental data using MgO–SiO2. While using CaO–SiO2 as a catalyst, non-linear kinetic model was found to fit with the experimental data better.