Comparative Assessment of Physico-chemical Characteristics of Balanites aegyptiaca (Desert Date) Biodiesel Blends and Conventional Diesel

The growing global energy demand and the environmental impact of conventional diesel impose the exploration of sustainable alternatives. This study assesses the physico-chemical properties of Balanites aegyptiaca (desert date) biodiesel blends (B20, B25, and B30) against conventional diesel (B0) and ASTM D6751 standards. Biodiesel was produced via alkali-catalyzed transesterification, achieving an 81.2% yield from seed kernels with 43.5% oil content. Important fuel properties, including density, flash point, kinematic viscosity, pour point, cloud point, and calorific value, were analyzed. The results shows that the blends have a higher density (850–860 kg/m³), elevated flash point (100–110°C), and increased viscosity (3.25–3.60 mm²/s) than diesel (830 kg/m³, 93°C, 2.60 mm²/s), with slightly lower calorific values (42.5–43.8 MJ/kg to 45.4 MJ/kg). While viscosity met ASTM D6751 limits (1.9–6.0 mm²/s), flash points were substandard (<130°C min). Cold-flow properties (pour point: -11.9 to -13.6°C; cloud point: -2 to -8°C) were inferior to diesel (-17°C; -15°C), indicating cold-climate working challenges. The B20 blend demonstrated an optimal balance between fuel properties and renewable content. Balanites aegyptiaca biodiesel is viable for diesel engines but requires additive treatment or blend optimization for cold regions. These findings support sustainable biofuel development in arid zones using non-food feedstocks.