Research on Unregulated Emissions from an Alcohols-Gasoline Blend Vehicle Using FTIR, HPLC and GC-MS Measuring Methods 2013-01-1345

Unregulated emissions have become an important factor restricting the development of methanol and ethanol alternative alcohols fuels. Using two light-duty vehicles fuelled with pure gasoline, gasoline blend of 10% and 20% volume fraction of ethanol fuels, gasoline blend of 15% and 30% volume fraction of methanol fuels, New European Driving Cycle (NEDC) emission tests were carried on a chassis dynamometer according to ECE R83-05. High performance liquid chromatography (HPLC), Gas chromatography - Mass spectrometry (GC-MS), Fourier transform infrared spectrometer (FTIR) were used to measure methanol, formaldehyde, acetaldehyde, acetone, benzene, toluene, xylene, ethylene, propylene, 1,3-butadiene and isobutene emissions in the exhaust during the NEDC.

The test results show that the methods of the integration of FTIR instantaneous values and the chemical analysis of bag sampling can both accurately measure formaldehyde, acetaldehyde, and benzene and toluene emissions in the vehicle exhaust. Comparing the instantaneous emissions and average emissions during the driving cycle of major pollutants, the good consistency of FTIR, HPLC and GC-MS measuring methods has been verified. The emissions deviations of various measurement methods are in the range of ± 10%.

During the first acceleration condition, the instantaneous emissions of methanol, formaldehyde, acetaldehyde, benzene, propylene and 1,3-butadiene have the highest peak. Then with the three-way catalyst lights off, the emissions values gradually reduce to nearly zero and remain until the end of the driving cycle.

As the alcohols proportion increasing in the fuel, CO₂ emissions in the exhaust remain basically the same, HC, CO and CH₄ emissions decrease slightly, NO_X emissions increases slightly, unburned methanol, formaldehyde and acetaldehyde emissions increase proportionally, benzene, toluene, ethylene, propylene, 1,3-butadiene and isobutene emissions decrease.