Comparative assessment for biodiesel production from low-cost feedstocks of third oil generation

Biodiesel offers a sustainable fossil fuel alternative, highlighting the importance of third-generation feedstocks like macroalgae and waste frying oils (WFO) from palm, sunflower, and corn. This study investigates their physicochemical properties using different feedstocks towards biodiesel standard specifications. The feedstocks were synthesised through transesterification process at operating parameters molar ratio of methanol to oil (3:1-12:1), catalyst concentration (0.5-3 wt %), reaction time (60-240 min), and reaction temperature (55-75 degrees C). The fatty acid compositions were analysed using GC-Fid shows Azolla filiculoides (54.0 %), Ulva lactuca (56.0 %), WFO palm (56.5 %), WFO sunflower (85.7 %) and WFO corn (82.7 %) biodiesels dominated by unsaturated fatty acids have good physicochemical properties such as densities (872-883 kg/m(3)), kinematic viscosities (3.52-5.3 mm(2)/s), cloud points (10 degrees C to -10 degrees C), pour points (8 degrees C to -12 degrees C), cetane numbers (44.4-57.9), heating values (38.60-41.68 MJ/kg), and iodine values (60.94-129.15 g I-2/100 g) meet the specification of biodiesel standards. This study reveals fatty acid profiles significantly impact the physicochemical properties of biodiesel. Among all feedstocks, Azolla filiculoides demonstrating particularly promising characteristics for biodiesel production. These findings advocate for the increased exploration of third-generation feedstocks in the quest for sustainable biodiesel production processes.