Adaptation and Engine Validation of an FTIR Exhaust Gas Analysis Method for C1-Based Potential GHG-Neutral Synthetic Fuels/Gasoline-Blends Containing Dimethyl Carbonate and Methyl Formate 2022-01-0569

The European Commission has released strict emission regulations for passenger cars in the past decade in order to improve air quality in cities and limit harmful emission exposure to humans. In the near future, even stricter regulations containing more realistic/demanding driving scenarios and covering more exhaust gas components are expected to be released. Passenger cars fueled with gasoline are one contributor to unhealthy air conditions, due to the fact that gasoline engines emit harmful air pollutants. One option to minimize harmful emissions would be to utilize specifically tailored, low emission synthetic fuels or fuel blends in internal combustion engines. Methyl formate and dimethyl carbonate are two promising candidates to replace or substitute gasoline, which in previous studies have proven to significantly decrease harmful pollutants. This is especially in regard to particle emissions, while offering beneficial properties for SI combustion, such as high octane rating and high laminar flame speed.

FTIR-analyzers are a viable option for measuring future-restricted emissions, such as methane, ammonia, and formaldehyde, simultaneously with currently restricted emissions like NO_x and CO. Such analyzers provide deep insight into gaseous emissions of an engine. However, the underlying method of evaluation must be adapted to the fuel and exhaust components to provide reliable, realistic, and reproducible data.

This paper provides an insight of how a currently available method of FTIR spectra analysis for gasoline can be adapted to synthetic fuels containing Dimethyl carbonate (DMC) and Methyl Formate (MeFo). To validate the new method for these two components, several synthetic fuels and blends with gasoline will be analyzed. Exhaust gases of a single cylinder research engine fueled with 100 vol% DMC, 100 vol% MeFo, 65 vol% DMC and 35 vol% MeFo, five different DMC-gasoline blends and one MeFo-gasoline blend is used. Additionally, two mixtures of alkylate gasoline with MeFo and one methanol-MeFo mixture is shown. Alkylate gasoline is chosen due to its reduced PN-emissions and chemical properties similar to synthetically produced gasoline.