Solar thermal pyrolysis of non-edible seeds to biofuels and their feasibility assessment

Highlights: • Solar thermal bio-refinery technology was demonstrated for biofuels production. • All three pyrolysed products were assessed for their feasibility as fuel candidates. • Pyrolytic zone for Jatropha seed biomass was in the range of 203–508 °C. • Presence of alkane, ester, alkene, & alkyne groups were confirmed in products. • Maximum of 20% bio-oil, 51% bio-char and 29% pyrolytic gas were obtained. - Abstract: The present study is focused on conversion of non-edible Jatropha seeds biomass to biofuels i.e., liquid, solid and gaseous fuels via solar thermochemical pyrolysis process. All the three products namely; (i) bio-oil (liquid) (ii) biochar (solid) and (iii) pyrolytic gas were characterized by means of TG (Thermo-gravimetric), FTIR (Fourier transform infrared), GC–MS (Gas chromatography mass spectroscopy), proximate and ultimate analysis; and assessed their feasibility as fuel candidates. It is explored that 20% maximum bio-oil yield was obtained with the average reactor temperature of 250–320 °C. The pyrolytic zone for the biomass was identified in the range of 203–508 °C. The ultimate analysis of the bio-oil revealed that the oil is rich in carbon (58.3%) and hydrogen (8.7%) with an average chemical composition of CH_1.79N_0.05O_0.40. Relatively lower oxygen content in the bio-oil favors for high heating value. Higher H/C ratio (1.79) and lower O/C ratio (0.4) of the bio-oil indicates its suitability as petroleum fuel for engine applications. The carbon compounds present in the bio-oil are from C7 to C28 which may represent the mixture of diesel and gasoline fuels. Finally, it is emerged from the study that all the three products are exibiting various favorable conditions to be employed as fuel candidates for different applications such as engines and boilers.