Waste coconut oil methyl ester with and without additives as an alternative fuel in diesel engine at two different injection pressures

The performance and emission from diesel engine using biodiesel from waste coconut oil (WCOO) with and without additives is accessed in this article. WCOO biodiesel is produced from coconuts which are not favorable to be consumed by humans due to degradation. B20, B40, B50, and B100 biodiesel blends of WCOO are prepared and performance and emission testing are done. B20 blend of biodiesel is added with 5%, 10%, and 15% of 1-hepatanol and the tests are repeated. Then, B20 is added with 5% of 1-hepatnol, n-butanol, and iso-butanol as additive and separate analysis for each additive in B20 is carried out in similar way. The injection pressure was kept constant at 225 bar throughout these experiments. Later, B20, B40, B50, and B100 blends of WCOO are used separately for engine performance and emission behavior at 175 injection pressure without adding any additive. Brake specific fuel consumption (BSFC) and brake thermal efficiency are the factors analyzed during engine performance analysis and CO, CO2, HC, and NO(x)exhaust are recorded during emission analysis. From the comparative study, the engine performance of diesel is seen to be better than any other combination of biofuels at both the pressures. Among blends without additive, B20 performed better than other blends, B20 with n-butanol performed better than B20 without additive, while B20 with iso-butanol did not show any significant advantage. At 175 bar injection pressure 7.5% extra BSFC and approximately 16% more emission is obtained than at 225 bar pressure.