Performances on engine-out emissions and combustion of ethylene glycol monobutyl ether palm oil monoester as a newtype biodiesel

Abstract

In order to enhance the effect of traditional biodiesel in reducing engine-out smoke formation, the introduction of other ether group into its molecule was attempted. Now a novel biodiesel named ethylene glycol monobutyl ether palm oil monoester is developed, which owns more environment-friendly than the traditional biodiesel. The fuel was synthesized with palm oil and ethylene glycol monobutyl ether, structurally identified through FT-IR, P1PH NMR and GPC analyses. Engine test results show that when a tested diesel engine is fueled with this biodiesel(B100) and its mixture with diesel fuel(B25) in place of 0# diesel fuel(B0), engine-out smoke emissions for B100 can be significantly decreased by 9%–54.6%, while CO, NOx, and unburned hydrocarbon emissions are also lessened 50.0%–66.7%, 25.7%–37.1%, and 45.5%–58.3%, respectively, compared with B0 under partial load modes. The similar situation was also adequate to B25. In the area of combustion performances, B100 is ignited earlier during diesel engine operation, so utilization of the new biodiesel can remarkably improve engine brake thermal efficiency. Because of certain amount of oxygen contained in the new biodiesel resulting in the low calorific value, the higher cetane number and shorter ignition delay, both engine in-cylinder pressure and its changing rate with crankshaft angle are increased to some extent for ethylene glycol monobutyl ether palm oil monoester, and the combustion of it can lead to a little higher heat release rate than diesel fuel.