AAAR 31st Annual Conference
October 8-12, 2012
Hyatt Regency Minneapolis
Minneapolis, Minnesota, USA
Abstract View
Characterization of Emissions Due to Internal Combustion of Nano-CeO$_2 Doped Diesel Fuel
YEVGEN NAZARENKO, Leonardo Calderon, Lin Zhang, Jim Zhang, Paul Lioy, Kian Fan Chung, Gediminas Mainelis, Rutgers, The State University of New Jersey
Abstract Number: 505 Working Group: Combustion
Abstract CeO$_2 nanoparticles are increasingly being used as a fuel-borne catalyst to improve diesel combustion efficiency. It is unknown whether the addition of nano CeO$_2 into diesel fuel alters physicochemical and toxicological properties of diesel exhaust particles. Here we characterized exhaust emissions resulting from combustion of nano-CeO$_2 doped diesel fuel in a one-cylinder electrical generator (Yanmar) under 100% load. Envirox$^(TM) CeO$_2 additive (Energenics Ltd., UK) was mixed with regular ultra-low sulfur diesel fuel at 0 ppm (0X of CeO$_2), 5 ppm (0.1X), 50ppm (1X – manufacturer’s recommendation), and 500 ppm (10X). A portion of the exhaust was directed into a 25 m$^3 stainless steel testing chamber where the exhaust mass concentration during characterization was maintained at approximately 300 µg/m$^3. A Scanning Mobility Particle Sizer and an Aerodynamic Particle Sizer were used to measure aerosol number concentrations. Gas monitors were used to analyze concentrations of CO, CO$_2, and NO$_x.
We observed that the total aerosol number concentration increased with increasing CeO$_2 concentration in the fuel: from 1.5 ×10$^5 cm$^-3 for diesel only (0X) to 3.6×10$^5 cm$^3 for 10X CeO$_2. Concurrently, the mean particle diameter by number decreased with increasing CeO$_2 concentration: from approximately 160 nm for diesel only (0X) to 100 nm for 10X CeO$_2 and the decrease was statistically significant. At the same time, CO$_2 concentration increased with moving from 0X to 10X of CeO$_2: from approximately 1300 ppm to approximately 2250 ppm. Increasing CeO$_2 concentration in the fuel also increased concentrations of NO$_x (from 4500 ppb to 10200 ppb) and CO (~4 to ~6.4 ppm) in the exhaust.
The results show that per mass basis the use of CeO$_2 additive leads to a reduced size of exhaust particles but might result in an increased concentration of ozone forming gases such as NO$_x. The results will be verified for total emissions basis.