Abstract
Third generation feedstocks and its constituent biofuels have shown promising results in the light of sustainable production and as a feasible fuel source for internal combustion engines. Hence, in this study, a third generation microalgae feedstock (scenedesmus quadricauda) biomass was cultivated sustainably using an in-situ tubular photo bioreactor and raceway pond to synthesize quintet carbon chained amyl alcohol using Ehrlich biosynthetic pathway. On analyzing the synthesized amyl alcohol, a homogenous mixture of a 20 % (vol/vol) amyl alcohol-diesel blend showed similarities with conventional diesel in their physio-chemical properties. This potential fuel source was analyzed though systematic experimentation at maximum throttle position condition in a light commercial vehicle compression ignition engine. The conducted experiments were directed by Response Surface Methodology coupled with Central Composite Design which delivered a set of influential and interactive responses on engine testing. At optimal operating condition, 0.7% rise in brake thermal efficiency and an increased specific fuel consumption of 5.6% is reported due to the lower heating value of the biofuel. Furthermore, a 55.8% and 5.4% drop in smoke and carbon monoxide emissions is observed. However, oxides of nitrogen emission increases by 31.7% for biofuel operation as a trade-off for the improved combustion characteristics achieved.