Abstract

                                In the current study, biodiesel properties of fatty acid methyl ester (FAME) derived from fats of four gamma-irradiated mutants (Cl801, Cl802 Cl803 & Cl804) and wild type (ClWT) of Chlorella sp. KM504965 were determined and compared with American Society for Testing and Materials (ASTM), European Norm (EN) and Indian standards (IS). Maximum concentration of saturated fatty acids (62.69%), monounsaturated fatty acids (36.29%) and polyunsaturated fatty acids (15.49%) recorded in ClWT, Cl801 and Cl803 respectively. The kinematic viscosity of Cl801 (4.88 mm2s-1), Cl802 (4.90 mm2s-1), Cl803 (4.73 mm2s-1), Cl804 (4.88 mm2s-1) and ClWT (4.92 mm2s-1) fits with ASTM, EN and IS. The density of Cl801 (0.83 gcm-3), Cl802 (0.84 gcm-3), Cl803 (0.78 gcm-3), Cl804 (0.80 gcm-3) and ClWT (0.81 gcm-3) was slightly lower than the standard limits (0.86 – 0.90 gcm-3). The high heating value of Cl801 (37.62 MJKg-1), Cl802 (38.15 MJKg-1), Cl803 (34.93 MJKg-1), Cl804 (36.44 MJKg-1) and ClWT (36.99 MJKg-1) were in accordance with ASTM standards. The iodine value was 47.38 mgI2 100g-1 (Cl801), 52.18 mgI2 100g-1 (Cl802), 50.87 mgI2100g-1 (Cl803), 47.04 mgI2100g-1 (Cl804), and 27.45 mgI2100g-1 (ClWT). The oxidative stability was 10.78 h (Cl801), 6.60 h (Cl802), 6.44 h (Cl803), 9.06 h (Cl804) and 39.83 h (ClWT). The cetane number of Cl801 (63.3), Cl802 (61.80), Cl803 (62.16), Cl804 (64.99) and ClWT (68.7) was greater than the standard values (61 to 65). It is concluded that the biodiesel from mutants could comply IS, ASTM, and EN and equivalent with biodiesel from vegetable oil.

Key words : Chlorella; Mutants; Fats; Biodiesel property; Viscosity; Density