The Survivability of Diesel Fuel Components in the Organic Fraction of Particulate Emissions from an IDI Diesel

A mass balance has been carried our between fuel and particulate SOF n-alkanes and the survivability of a range of fuel n-alkanes was determined, Similarly the survivability of fuel PAH was determined and compared with the equivalent boiling point n-alkanes. A Petter AA1 single cylinder IDI engine was used with direct particulate sampling at 50C from the exhaust. The PAH and n-alkane fuel component survivabilities were mainly below 0.1%, indicating that unburnt fuel was the dominant source of particulate PAH. However, at maximum power there was an order of magnitude difference in the survivabilities of some PAH and n-alkanes. This indicated a possible pyrosynthesis source of PAH or a role of the engine and exhaust deposits in releasing PAH. The results confirm previous conclusions from test on a DI engine.