Polycyclic Aromatic Hydrocarbons in Particulate Matter Emitted by the Combustion of Diesel and Biodiesel

Abstract

Two sets of experiments were performed for collected particulate mass emitted directly from the exhaust of diesel engines burning diesel and biodiesel fuels: First, a diesel truck was used in the field, and in the second test, a similar diesel engine was used in the laboratory. The mass of particles and polycyclic aromatic hydrocarbons (PAH) was determined. No reduction was observed in the mass of particles per min using biodiesel relative to that produced when burning diesel. Pyrene and phenanthrene showed the highest mass concentrations in diesel and biodiesel in both tests. Reductions in these PAHs greater than 80% (in the truck field test) and 35% ± 11% (in the engine laboratory test) were observed when using biodiesel in any mixture thereof, with respect to diesel. The mean ± standard deviation of the ratios of BaA/(BaA + Chry) and (BbF + BkF)BghiP for diesel emissions were consistent with the literature. Four ratios amongst PAHs were proposed, with relative standard deviation < 10%, which suggests that these ratios could be used as emission markers for diesel and animal biodiesel blends (<B20).

Keywords:

• Biodiesel
• Diesel
• PAH diagnostic ratios
• Particles
• Polycyclic aromatic hydrocarbons

ACKNOWLEDGMENTS

VHBL acknowledges CONACyT for scholarship to develop the doctorate studies in the Posgrado de Ciencias de la Tierra, UNAM. We would like thank Samuel Miguel Rico, Hugo Barrera, José Ramón Hernández, Wilfrido Gutiérrez, Manuel García, Alfredo Rodríguez, Delibes Román, and Saúl Armendariz for their technical assistance. We thank Claudio Amescua and Pietro Villalobos for their writing assistance. We thank the Proyect PICS08-31 of ICyT-GDF, CONTACyT-SEMARNAT 23600 and Proyect PAPIIT IN116810-3 for the funded in the development of this study.

Notes

N – number of observations.

^a Manoli et al. (2004).

^b Sicre et al. (1987).

^c Pandey et al. (1999) and Park et al. (2002).

^d Westerholm et al. (1991) and Ströher et al. (2007).

^e Li and Kamens (1993).

^f This study involving truck and engine tests.

SD – Standard deviation, s – PAH median ratios were significant different (p ≤ 0.05) among truck and engine tests and therefore the median neither the mean would not be representative values.

*PAH ratios only consider the field tests, since BghiP was not detected in the particles emission collected in the laboratory tests.

RSD – Relative standard deviation.

*PAH ratio did not consider data from laboratory tests with biodiesel, since BghiP was not detected in their emissions.