Diesel surrogates

The ANL catalyst (not identified, but presumably a Pt supported on Gd-doped ceria) was also successfully used for ATR of diesel fuel. Tests of three different types of diesel fuels (n-Cie, low-sulfur diesel, and regular diesel) showed complete conversion of hydrocarbons at 800°C. The diesel surrogate n-Ci6 yielded 60% H2 on a dry, N2-free basis at 800°C, whereas the other two diesel fuels required higher temperatures (>850°C) to yield similar levels of H2 in the product gases. Similar or improved H2 yields from diesel ATR were observed with a microchannel monolith catalyst, compared with extruded pellets in a fixed-bed reactor. ... 

Alvarez-Galvan, M.C., Navarro, R.M., Rosa, F., Briceno, Y., Ridao, M.A., and Fierro, J.L.G. Hydrogen production for fuel cell by oxidative reforming of diesel surrogate Influence of ceria and/or lanthana over the activity of Pt/Al203 catalysts. Fuel, 2008, 87 (12), 2502. 

Dreyer et al. [33] investigated the oxidative steam reforming of diesel surrogates over wash-coated ceramic monoliths carrying 5 wt.% rhodium supported by y-alumina. The conversion of M-decane dropped with increasing S/C ratio because the reaction temperature decreased significantly. The beneficial effect of... 

The fate of four petroleum mixtures has been evaluated using three approaches—evaluating the fate of (1) indicator chemicals, (2) the mixture of the whole with a surrogate, and (3) the hydrocarbon mixture as a whole. The four mixtures were crude oil, JP-5, mineral spirits, and diesel. The choice of approach requires the consideration of availability and quality of data on the mixture, the mobility and toxicity of the mixture, and the availability of site data (Custance et al. 1992). 

Table 2 shows the thermodynamics of the three major carbon-forming reactions (6)-(8), at 600°C, 1 atm, using n-Cig and i-Cg as surrogates of diesel and gasoline, respectively. 

Sufficiently similar mixtures. Another approach is to use surrogate data on one whole mixture to conduct the risk assessment of another. This applies the concept of sufficient similarity, defined as 2 mixtures close in chemical composition where there are small differences in their components and in the proportions of their components. Key issues for similar mixtures include assessing the similarity of analytical chemistry and toxicological data for mixtures. In this case, an RfD, RfC, or slope factor could be calculated for the mixture of concern using data on a sufficiently similar mixture. This concept is also used in specific applications to groups of similar mixtures that are produced by similar processes, for example, the comparative potency method as applied to diesel exhaust emissions (Lewtas 1985,1988 Nesnow 1990). 

However, since these transportation fuels are complex mixtures containing a wide range of hydrocarbons, aromatics, and olefins, simple hydrocarbons such as isooctane (C8 hydrocarbon), dodecane (C,2 hydrocarbon), and hexadecane (C16 hydrocarbon) have been used as representative surrogate fuels for gasoline, jet fuel, and diesel, respectively, in order to better understand the chemistry involved and... 

As with some of the chronic animal studies, exposures in most of the occupational miner cohorts consist of exposure to radon and radon progeny in the presence of other contaminants such as uranium ore dust, diesel-engine exhaust, or other mine pollutants. Only a few studies of lung cancer associated with environmental exposures to radon and radon daughters have been reported. These studies are primarily case-control or case-referent studies that involve a small number of subjects and have exposure estimates that are based on either surrogates for measurements or limited measurements. Additional studies of the extent of the hazard associated with environmental radon daughter exposures would provide useful information since radon is an ubiquitous substance, especially as they compare to estimates of the human health hazard based on the occupational setting. 

Thormann et cd. [9] investigated the performance of Rh/Al203 and Rh/Ce02 catalysts in hexadecane steam reforming in the low-temperature range from 400 to 700 °C. Full conversion of hexadecane, which served as surrogate for diesel fuel, was achieved at a S/C ratio of 4.0 and 700 °C reaction temperature only over the Ce02-supported sample, which also showed short-term stability for 16h, and the alumina-supported sample suffered from rapid deactivation. 

Instantaneous maps of the mixture fraction, temperature, and main combustion products (H2O, CO2, CO) are shown in Figure 7.4 for the n-heptane. N-heptane is a fuel commonly used in engines. Its cetane number is approximately 56, which is typical for diesel fuel, because its properties of ignition and combustion are similar to those of diesel fuel [7]. The n-heptane has received substantial interest because it is a major component of the primary reference fuel (PRF) in internal combustion engine studies [6] and is considered a surrogate for liquid hydrocarbon fuels used in many propulsion and power generation systems [8]. 

The inhibition of SCR reactions by HC were studied in the laboratory flow reactor at temperatures around 200-300 °C typical of diesel vehicles over the FTP-75 drive cycle. From an analytical speciation of HC during a typical diesel cold start event, reasonable surrogates for laboratory testing were determined to be propylene (for olefins), benzene (for aromatics), and n-decane (for paraflhns). As described earlier, the initial Cu and Fe SCR catalysts contained beta zeolite. Laboratory evaluations demonstrated that co-feeding any of the three hydrocarbon types had a... 

The steam reforming of hydrocarbons such as diesel has been demonstrated in MSRs whose mechanical stability has been proven at high temperature (750-850 °C). Most of the configurations consist of co-current flow diesel steam reforming combined with combustion of fuel cell anode and/or cathode off-gas surrogate. Full conversion was obtained in all cases. Power equivalent of these systems varied between 2-5 kW thermal energy of the hydrogen produced and 10 kW thermal input of the diesel feed [4,73]. However, the most advanced... 

Battin-Leclerc, F. Detailed chemical kinetic models for the low-temperature combustion of hydrocarbons with application to gasoline and diesel fuel surrogates. Prog. Energy Combust. Sci. 34, 440-498 (2008)... 

Malik, A., Schramm, J., Nielsen, C., Lpvas, T. Development of surrogate for Fischer-Tropsch biofuel and reduced mechanism fiu combustion in Diesel engine. SAE Technical Paper 2013-2001-2599 (2013)... 

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