Properties of jatropha hybrid seed oil and its suitability as biodiesel feedstock

Seed oil was extracted using n-hexane as solvent in the Soxhlet extraction method where oil content varied from minimum (37.44%) in Hybrid-6 (first filial generation between parents P-2 and P-3) to maximum (47.82%) in Hybrid-12 (first filial generation between parents P-3 and P-6) among seed kernel of different hybrids. Density, specific gravity, and refractive index of oil showed very little but significant differences among the seed samples. Seed oil of parental genotype P-5 had the highest free fatty acid (FFA) content (5.50%) and the lowest (1.25%) was found in parent P-4. Seed oil of Hybrid-11 had the highest FFA content (6.51%) and the lowest was in Hybrid-6 (1.11%). Seed oil of parent P-2 had the highest iodine value (111.50 mg/g oil) and the lowest was (99.10 mg/g oil) in P-5. The lowest saponification value was obtained from seed oil of parent P-4 (184.19 mg KOH/g) and the Hybrid-11 (174.97 mg KOH/g oil). Maximum higher heating value (41.00 MJ/kg) was obtained from the seed oil of Hybrid-3 and Hybrid-14. The cetane number ranges from 49.59 to 52.30 among the oils of parental genotypes and 50.61 to 60.71 among hybrids. The result from the present study provides information on suitability of jatropha hybrid seed oil as feedstock for biodiesel production.