Evaluation of Particle Emissions Emitted from a Light-duty Diesel Vehicle Equipped with Retrofit Ceria and Platinum Partial Flow Diesel Particulate Filters

Abstract

Abstract With increasingly stringent emissions standards, the reduction of harmful exhaust gases and solid particles has become a primary concern for diesel vehicles. This study focuses on a light-duty vehicle equipped with a 2.5L 4-cylinder common rail direct diesel injection engine, evaluated on a chassis dynamometer under four urban driving cycles and one extra-urban cycle of the new European driving cycle (NEDC). The vehicle's emissions were assessed using B10, B20, and B100 fuels in two scenarios: without a retrofit partial filter diesel particulate filter (P-DPF) and with P-DPFs coated with ceria and platinum. Comparing the use of biodiesel, B100 demonstrated a significant reduction of approximately 50% in particulate mass (PM) and particulate number (PN). Furthermore, the results indicated that the utilization of the partial flow DPF led to a PM emissions reduction exceeding 60% and a particle number reduction of up to 45%. Additionally, the installation of a diesel oxidation catalyst (DOC) resulted in reductions of total hydrocarbon (THC) and carbon monoxide (CO) emissions by up to 59% and 81% respectively, compared to the baseline fuel emissions. However, the installation of the retrofit P-DPF and DOC did not have a significant impact on carbon dioxide (CO2) and nitrogen oxides (NOx) emissions. In terms of catalytic coating, the ceria catalyst emerged as a promising and cost-effective alternative to platinum catalysts for reducing pollutant emissions from diesel vehicles. Overall, this study highlights the effectiveness of utilizing B100 biodiesel and the after-treatment system including P-DPFs and DOCs in mitigating particulate matter and certain gaseous emissions, emphasizing the potential of ceria catalysts as a viable option in emission reduction strategies for diesel vehicles.