Promotion of the NO-to-NO2 Conversion of a Biofueled Diesel Engine with Nonthermal Plasma-Assisted Low-Temperature Soot Incineration of a Diesel Particulate Filter

High-concentration biodiesel-diesel fuel blends are an alternative fuel widely used for compression ignition engines. However, commercial diesel engines are not designed and set up for high-concentration biodiesel-diesel fuel blends. Hence, the aim of this research was to investigate the nonthermal plasma (NTP) activities during an NOx reduction and the soot characteristics on an unmodified diesel engine (Euro V) that is fueled with various biodiesel blends with diesel under a low exhaust gas temperature (<250 °C). The experiment found that the soot composition of biodiesel fuel produces lower levels of soot when compared with diesel, in terms of both number and mass. In addition, the activation energies (Ea) of carbon oxidation under an oxygen atmosphere were found to be approximately 154.57–173.64 kJ/mol.