Exhaust emissions and combustion performances of ethylene glycol monomethyl ether palm oil monoester as a novel biodiesel
A novel biodiesel named ethylene glycol monomethyl ether palm oil monoester was developed. This fuel owns one more ester group than the traditional biodiesel. The fuel was synthesized and structurally identified through FT-IR, P1PH NMR analyses and GPC. Engine test results showed that when a tested diesel engine was fueled with this biodiesel in the place of 0# diesel fuel, engine-out smoke emissions decreased by 69.0 to 89.3%, and nitric oxide (NOx) also lessened significantly, but unburned hydrocarbon (HC) and carbon monoxide (CO) emissions generally do not change noticeably compared with pure diesel fuel. In the area of combustion performances, both engine in-cylinder pressure and its changing rate with crankshaft angle were increased to some extent for ethylene glycol monomethyl ether palm oil monoester because of the higher cetane number and shorter ignition delay. Due to certain amount of oxygen contained in the new biodiesel resulting in the low calorific value, the engine thermal efficiency dropped by 14.4% at record level when fueled with the biodiesel, which needs to be improved in the future.
Key words: Biodiesel, ethylene glycol monomethyl ether palm oil monoester, engine-out emissions, combustion.