Diesel particulate extracts

Diesel Particulate Extract PAHs (8) PAH (23) Nitro-PAHs (18)... 

Figure 2. Gas chromatogram of A, PAH fraction of diesel particulate extract (Sl-C2) and By its HPLC subfraction C (S1-C2). GC conditions 45- X 0.35-mm id SE54 glass capillary column flame ionization detector temperature, 110°C for 2 min, programmed to 170°C at 10°/min, to 212°C at 3°/min, to 278°C at 8°/min. Peak identities 1, phenanthrene 2, anthracene 3-6, methylanthracene/-phenan-threne 7, 2-phenylnaphthalene 8-10, dimethylanthracene/-phenanthrene 11, fluoranthene 12, aceanthrylene/acephenanthrylene 13, pyrene 14-15, trimethylan-thracene/-phenanthrene 16, benzo [ghi]fluoranthene 17, benzo[a/anthracene 18, triphenylene 19, chrysene 20, benzo[b]fluoranthene 21, benzo[]]fluoranthene ...

Schuetzle D, Lee FSC, Prater TJ (1981) The identification of polynuclear aromatic hydrocarbon (PAH) derivatives in mutagenic fractions of diesel particulate extracts. Intern JEnviron Anal Chem 9, 93-144. 

One of the earliest works using HPLC-DAD for the identification of the large PAHs involved the analysis of a diesel particulate extract [16-18]. About a dozen LPAHs were found. The identifications made were later correlated to the observed mutagenicity of this diesel particulate. A carbon-black extract, obtained from the same carbon black was examined by HPLC-DAD. The DAD, as well as a much larger collection of standard compounds, allowed the identification of around 20 more LPAHs than in earlier studies of this same material. 

The methanol fractions ( 4) of two of the light-duty diesel particulate extracts were also analyzed by HRGC/MS and high resolution mass spectrometry (HRMS) in an attempt to tentatively... 

Previous studies have shown that most of the direct-acting Salmonella typhimurium mutagenic activity (>50%) in diesel particulate extracts is concentrated in chemical fractions which contain compounds of moderate polarity (1-4). These moderately-polar fractions have been found to consist... 

Sample Fractionation - Figure 1 shows the HPLC chromatogram for a diesel particulate extract and elution times for some standards. The sample has been divided into eight fractions. 

Figure 1. HPLC Chromatogram for A Light-Duty Diesel Particulate Extract... 

Chemical Composition of the Moderately-Polar Fractions - We have recently reported that the oxy-PAH account for most of the mass contained in the moderately-polar fractions for a light-duty diesel particulate extract(9). We have undertaken a similar analysis for the sample described in this work (figure 1) and found that it is qualltlvely similar but quantitatively different than that previously described for emissions collected from another light duty diesel englne(9). It can be concluded from these results that ... 

Identification of Nitro-PAH - Figure 2 shows GC /ND chromatograms for the analysis of three moderately polar fractions of the diesel particulate extract shown... 

Nitroaromatic Compounds in The Direct-Acting Mutagenicity, of Diesel Particulate Extracts," J. of Applied Toxicology, 1981, 1, 54. 

Salmeen, I., Pero, a., Riley, T., Hampton, C., Prater, T., Corse, R. and Schuetzle, D., "Identification and Rigorous Quantitation of Direct-Acting Ames Assay Mutagens in Diesel Particulate Extracts , to be presented at the Sixth International Symposium on Polynuclear Aromatic Hydrocarbons, Columbus, Ohio (Oct. 27-29, 1982). 

Recently, considerable work has been performed on the identification of PAH-derivatives in diesel particulate extracts using a combination of preparative HPLC separation and GC-HS or HR-I1S analysis CSchuetzle et al. (46)). Whereas the composition of the non-polar fraction in terms of aliphatic and polyaromatic hydrocarbons has been well characterised, the compounds present in the moderately to highly polar fractions had not been identified before. 

TABLE 10.33 Concentrations of Selected Nitroarenes in Extracts of Diesel Particulate POM b... 

Bagley, S. T., S. L. Stoltz, D. M. Becker, and R. E. Keen, "Characterization of Organic Extracts from Standard Reference Materials 1649, Urban Dust/Organics, and 1650, Diesel Particulate Matter, Using a Microsuspension Assay. A WHO/IPCS/CSCM Study, Mutat. Res., 276, 81-86 (1992). 

Robbat, A., Jr., N. P. Corso, P. J. Doherty, and M. H. Wolf, Gas Chromatographic Chemiluminescent Detection and Evaluation of Predictive Models for Identifying Nitrated Polycyclic Aromatic Hydrocarbons in a Diesel Fuel Particulate Extract, Anal. Chem., 58, 2078-2084 (1986). 

Clark, C.R. and Vigil, C.L. (1980). Influence of rat lung and liver homogenates on the mutagenicity of diesel exhaust particulate extracts, Ihxicol. AppL Pharmacol. 56,110. 

Kelly GW, Bartle KD, Clifford AA, et al. 1993. Identification and quantitation of polycyclic aromatic compounds in air particulate and diesel exhaust particulate extracts by LC-GC. J Chromatogr Sci 31(3) 73-76. 

Diesel particulate Diesel part, extract SRM 1650a SRM 1975 ... 

Consequently, the vast majority of SCF applications are based on CO2 near the GL critical point, with a possible admixture to support the ability for solvating dipolar components. The extraction of carcinogenic aromatic hydrocarbons and their nitro derivatives from diesel particulates by CO2 + toluene or methanol SCF can serve as an example. CO2 based SCF also helps in cleaning polyethylene from undesired polymer additives. In a similar way one can consider technologies focused on so called h q)er-coal, an extremely pure and environment friendly fuel for turbines in power plants. Recently, the first power plants based on this idea are being constructed in China. The removal of pesticides from meat, decaffeinated coffee and denicotinized cigarettes are the next society-relevant applications. Noteworthy is the h q)er-oxidation with supercritical water and bitumens extraction based on supercritical toluene. The latter system is also used for the liquefaction of coal. ... 

Hawthorne, S. B.,etal. (1992) Extraction of polycyclic aromatic hydrocarbons from diesel particulates, J. Chromatography, 609, 333-340 Cansell, F., andRey, S. (1998) Thermodynamic aspects of supercritical fluids... 

The carbon content and amount of particulate matter to which PAHs are sorbed influences their extractability. " Recoveries of PAHs from particulates decrease with increasing carbon content and amount of particulate matter. Diesel particulate matter, from which PAHs are extremely difficult to recover, is about 80% carbon. 

MAE has been applied to the extraction of PAHs from diesel particulate matter (SRM 1650). The high carbon content of diesel particulate matter results in extremely tight binding of PAH and very low extraction recoveries. Results comparable to certified values were obtained when DCM was used as the solvent at 400 W and triplicate 20 min extractions. 

Pineiro-Iglesias, M., Lopez-Mahia, P., Vazquez-Bianco, E., Muniategui-Lorenzo, S., and Prada-Rodriguez, D., Problems in the extraction of polycyclic aromatic hydrocarbons from diesel particulate matter, Polycyclic Aromat. Compd., 22, 129-146, 2002. 

Chee KK, Wong MK, Lee HK (1997) Microwave-assisted solvent extraction of air particulates for the determination of PAHs. Environ Monit Assess 44 391 08 Christensen A, Ostman C, Westerholm R (2005) Ultrasound-assisted extraction and on-line LC-GC-MS for determination of polycyclic aromatic hydrocarbons (PAH) in urban dust and diesel particulate matter. Anal Bioanal Chem 381 1206-1216 Cortazar E, Bartolome L, Delgado A, Etxebarria N, Fernandez LA, Usobiaga A, Zuloaga O (2005) Optimisation of microwave-assisted extraction for the determination of nonylphenols and phfhalate esters in sediment samples and comparison with pressurised solvent extraction. Anal Chim Acta 534 247-254... 

The method commonly used for preparation of diesel particle extracts employs a Soxhlet extaction apparatus with dichloromethane as the extracting solvent. This procedure has been found optimal for extraction of the mutagenic components adsorbed to the particulate (4). Most of our studies have been conducted with an extract prepared from particulate collected by electrostatic precipitation, which allowed the collection of a moderate amount of material in a short period of time (5). Extracts were also prepared from diesel particulate collected by two other methods. These extracts and the methods of particle collection are described in Table 1. The baghouse filter apparatus was used to obtain a large quantity of particulate required for a skin-painting carcinogenesis assay (6). This method involves collecting the particulate from hot undiluted... 

Schuetzle, D. and Perez, J. M., A CRC Cooperative Comparison of Extraction and HPLC Techniques for Diesel Particulate Emissions, Proceedings of the 74th Annual Meeting of the Air Pollution Control Association, Paper 81-56.4, Philadelphia, PA. (June 16-21, 1981). 

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