Abstract
Recently, many leading car manufacturers have started to develop new types of vehicles based on alternative fuel technologies. Biodiesel fuels may be a good solution in the search for sustainable energy sources for the transportation sector. With the concerns for the environmental impacts becoming larger, emissions of airborne particulate matter (PM) from biodiesel and diesel oil combustion have recently gained more attention because of their close association with health problems and environmental impacts, while such effects are not fully understood yet. Particulate emissions of transport systems and their impact on the atmosphere are currently acknowledged to be the largest source of uncertainties in understanding the traffic impact on regional environment and global climate. The main reason is the significant role which combustion aerosol plays in air quality, radiative and chemical balance, and smog/fog/cloud formation. In urban areas transport-emitted particles are considered as a dangerous pollutant with respect to human health, especially in the regions of public transportation (near roads, airports and harbors). They may cause and enhance respiratory, cardiovascular, and allergic diseases. In this study, PM samples were collected in the exhaust of different diesel engines operated at the Technical University of Munich in Germany and at the National University of Singapore. Two types of fuel, B7 diesel and rapeseed oil biodiesel, were used in the German study, while the other set of samples obtained from Singapore consisted of PM emissions from different diesel/biodiesel blends, ranging from 0 to 100% biodiesel content. A variety of chemical species were identified and quantified in the PM samples by various analytical methods.