Erythrina indica seed oil: sustainable biodiesel production

Abstract

This study examines the viability of Erythrina indica (Indian Coral Tree) seed oil, a non-consumable resource, as a substrate for second-generation biodiesel production. The seeds exhibited a notable oil content of 38 % (w/w). Crude oil was transformed into Fatty Acid Methyl Esters (FAMEs), referred to as EISOMEs (Erythrina indica Seed Oil Methyl Esters), by a base-catalyzed transesterification process using 1% KOH, resulting in a substantial practical yield of 90.2%. ¹H-NMR spectroscopic investigation validated the conversion, with an estimated result of 92.46%. The produced biodiesel underwent a thorough assessment of its fuel characteristics. Significant discoveries encompass an extraordinarily elevated Cetane Number (58.2), a high Flash Point (172°C), and a kinematic viscosity of 3.6 mm²/s, all of which conform to the stipulations of international standards including ASTM D6751, BIS 15607, and EN 14214. The Higher Heating Value was established at 39.6 MJ/kg, while the Cloud Point was recorded at 2.6°C. This work offers a comprehensive examination of these features, linking them to the distinctive fatty acid profile of the feedstock, and compares them with recognized non-edible feedstocks. The findings strongly suggest that Erythrina indica is a very viable and competitive feedstock for the production of sustainable, high-quality biodiesel, necessitating further exploration of its agronomic and economic potential.