PAHs emissions of alternative fuels: A comparative analysis of biodiesel and diesel

摘要

With mutagenic and carcinogenic potential, polycyclic aromatic hydrocarbons (PAHs) from mobile source exhaust have contributed to a substantial share of air toxics. In order to compare the PAHs emissions and their carcinogenic potencies from diesel, biodiesel (B100) and its blend (B20), an experimental study has been carried out on a direct-injection turbocharged diesel engine. The particle-phase and gas-phase PAHs from engine exhaust were collected by fiberglass filters and “PUF/XAD-2/PUF” cartridges respectively, then the PAHs were determined by a Gas Chromatograph/Mass Spectrometer (GC/MS). The results indicated that comparing with diesel, using B100 and B20 can greatly reduce the total PAHs emissions of diesel engine by 19.4% and 13.1% respectively. The Benzo[a]Pyrene (BaP) equivalent of PAHs emissions were also decrease by 15.0 ％ with the use of B100. The emissions of total PAHs, especially particle-phase PAHs, had the close correlation with particulate matter (PM) emissions for three fuels, furthermore, the correlation became more significant when using biodiesel.