Thermal behaviours at low and high temperature of biodiesels produced from beef tallow and corn oil

The thermal behaviours and kinetics of biodiesels produced from beef tallow and corn oils were examined by using thermal analysis techniques (TG-DTG/DSC) at different heating rates in this study. The biodiesels were analysed with H-1-NMR and GC-MS techniques. It was seen that the biodiesel samples are composed of both saturated (Myristic acid C14:0, palmitic acid C16:0, stearic acid C18:0,) and unsaturated (Palmitoleic acid C16:1, oleic acid C18:1, linoleic acid C18:2) FAMEs from GC-MS analysis. Kinetic parameters for the combustion process of biodiesels were determined by using the iso-conversional model-free methods, KAS and FWO methods. The activation energy of beef-tallow biodiesel from KAS method is 86.11 kJ mol(-1), and from FWO method is 83.52 kJ mol(-1). The activation energy of corn-oil biodiesel from KAS method is 79.12 kJ mol(-1), and from FWO method is 90.07 kJ mol(-1). It was figured out that the activation energies of the biodiesel samples have values close to each other, and controlling reaction mechanism for both biodiesel samples by using master-plot method are power law (P-4). It was obtained CP (cloud point) and CFPP (cold filter plugging point) values from DSC analysis. CP values of biodiesel from beef tallow and corn oil are 16.1 degrees C and - 5.5 degrees C, respectively. CFPP values of biodiesel from beef tallow and corn oil are - 11.2 degrees C and - 6.7 degrees C, respectively. It was obtained from TG-DSC analysis that the origins of biodiesel samples on thermal behaviours are dominant at low temperatures (< 0 degrees C), yet the origins are not important at high temperature, and the combustion properties are the same as each other.

Automated summary

This study investigated the thermal behaviors and kinetics of biodiesels derived from beef tallow and corn oils. The results revealed that the biodiesel samples contained both saturated and unsaturated fatty acid methyl esters. The activation energies for the combustion process of biodiesels were determined and found to be similar for both beef-tallow and corn-oil biodiesels. Additionally, the cloud point and cold filter plugging point values were obtained from the analysis.