Utilization of Chlorella vulgaris methyl ester blend with diethyl ether to mitigate emissions of an unaltered single...

The present work emphasizes the viability of methyl ester production, characterization, and utilization of third-generation biofuel from Chlorella vulgaris microalgae. The presence of methyl oleate (C₁₉H₃₆O₂) in the Chlorella vulgaris methyl ester (CVME) algae signifies the existence of higher oxidation stability and prone to peroxidation. The single-stage transesterified CVME algae contains majorly (C-H) functional group trailed by (C = O), (C-O), (O-CH₃), (C-O-C) with the elemental compositions of 66.80% carbon, 11.80% of hydrogen, and 21.40% of oxygen. Performance, combustion, and emission parameters of this methyl ester with diethyl ether blends were investigated in a medium duty compression ignition (CI) engine with the baseline of diesel, neat Chlorella vulgaris oil (NCVO), and CVME. Findings revealed that the binary blend of CVME70 + DEE30 is optimal than CVME80 + DEE20 and CVME90 + DEE10. At maximum load, the brake thermal efficiency of the engine fuelled with CVME70 + DEE30 is 28.91%, whereas for diesel, it is 32.74%. Furthermore, the attained in-cylinder pressure and heat release rate of the binary fuel blends are comparatively higher than CVME and NCVO. Besides, there was a decrease in the emissions of unburned hydrocarbons, carbon monoxide, and smoke opacity, whereas the increasing level of NO emission was observed with CVME and binary fuel blends in compared to diesel. In conclusion, the research findings show's that the binary fuel combination of CVME70 + DEE30 exhibits improved performance with reduced emissions and makes it viable for utilization as a diesel substitute in CI engines without requiring any modifications.