Fuel components

To evaluate the real behavior of fuels in relation to the segregation effect, the octane numbers of the fuel components can be determined as a function of their distillation intervals In this manner, new characteristics have been defined, the most well-known being the delta R 100 (A7 100) and the Distribution Octane Number (DON). Either term is sometimes called the Front-End Octane Number . 

Outside of carbon monoxide for which the toxicity is already well-known, five types of organic chemical compounds capable of being emitted by vehicles will be the focus of our particular attention these are benzene, 1-3 butadiene, formaldehyde, acetaldehyde and polynuclear aromatic hydrocarbons, PNA, taken as a whole. Among the latter, two, like benzo [a] pyrene, are viewed as carcinogens. Benzene is considered here not as a motor fuel component emitted by evaporation, but because of its presence in exhaust gas (see Figure 5.25). 

Gas produced by oxidizer other than that formed by reaction of oxygen and fuel components. 

Thermochemical Liquefaction. Most of the research done since 1970 on the direct thermochemical Hquefaction of biomass has been concentrated on the use of various pyrolytic techniques for the production of Hquid fuels and fuel components (96,112,125,166,167). Some of the techniques investigated are entrained-flow pyrolysis, vacuum pyrolysis, rapid and flash pyrolysis, ultrafast pyrolysis in vortex reactors, fluid-bed pyrolysis, low temperature pyrolysis at long reaction times, and updraft fixed-bed pyrolysis. Other research has been done to develop low cost, upgrading methods to convert the complex mixtures formed on pyrolysis of biomass to high quaHty transportation fuels, and to study Hquefaction at high pressures via solvolysis, steam—water treatment, catalytic hydrotreatment, and noncatalytic and catalytic treatment in aqueous systems. 

American Petroleum Institute, Alcohols and Ethers-A Technical Assessment of Their Application as Duels and Fuel Components, API Pubhcation 4261, American Petroleum Institute, Washington, D.C., July 1988. 

Exhaust emissions of CO, unbumed hydrocarbons, and nitrogen oxides reflect combustion conditions rather than fuel properties. The only fuel component that degrades exhaust is sulfur the SO2 concentrations ia emissions are directly proportional to the content of bound sulfur ia the fuel. Sulfur concentrations ia fuel are determined by cmde type and desulfurization processes. Specifications for aircraft fuels impose limits of 3000 —4000 ppm total sulfur but the average is half of these values. Sulfur content ia heavier fuels is determined by legal limits on stack emissions. 

Attack on metals can be a function of fuel components as well as of water and oxygen. Organic acids react with cadmium plating and 2inc coatings. Traces of H2S and free sulfur react with silver used in older piston pumps and with copper used in bearings and brass fittings. Specification limits by copper and silver strip corrosion tests are requited for fuels to forestall these reactions. 

In contrast to carbon monoxide, small hydrocarbon molecules and soot that result from incomplete conversion of the hydrocarbon fuels, nitric oxide and nitrogen dioxide, are noxious emissions that result from the oxidizer—air. However, fuel components that contain nitrogen may also contribute, in a lesser way, to the formation of the oxides of nitrogen. 

Residues may also be processed by removing carbon. These processes include deasphalting and coking, which produce usable liquid fuel components while rejecting a carbon-rich phase (asphalt or coke). 

Commercial Mononitrophenol. Yel cryst mass mp about 45° mostly ortho- with some para-nitrophenol. Can be prepd by the nitration of phenol with dil nitric acid (1 3) at a temp below 35° (see Ref, p 283). Although it does not possess expl properties and does not gelatinize NC, it has been used as the fuel component of some commercial expls. It forms salts, some of which are weak expls which were used in expl compns, for example, Voight Explosives (qv)... 

The United States Environmental Protection Agency (U.S. EPA) has identified several hundred MTBE-contaminated sites that have performed treatment of soil and groundwater to remove or destroy MTBE.1 Many of these sites have also treated other fuel components, primarily benzene, toluene, ethylbenzene, and xylene (BTEX), and some have treated fuel oxygenates other than MTBE. Although others have reported about treatment technologies for MTBE cleanup,2 only limited information has been published about cleanup of other oxygenates. These oxygenates include ether compounds, such as ethyl tert-butyl ether (ETBE), tert-amyl methyl ether (TAME), diisopropyl ether (DIPE), and tert-amyl ethyl ether (TAEE), as well as alcohol compounds, such as tert-butyl alcohol (TBA), tert-amyl alcohol (TAA), ethanol, and methanol. 

The aqueous component from the fossil fuel component is seperated. The fossil fuel produced is significantly reduced in sulfur and salts. The aqueous effluent component is enriched in inorganic salts and inorganic sulfur molecules. 

Baynes R.E., et al., Mixture effects of JP-8 additives on the dermal disposition of jet fuel components, Toxicol. Appl. Pharmacol., 175, 269, 2001. 

Fig. 9.8 Schematic overview of the possible transformations of bioethanol into chemicals or fuel components. (Adapted from [79]).

Dauble DD, Carlile DW, Hanf RW, Jr. 1986. Bioaccumulation of fossil fuel components during single-compound and complex-mixture exposures of Daphnia magna. Bull Environ Contain Toxicol 37 125-132. 

Howe, G.B., Mullins, M.E., and Rogers, T.N. Evaluation and prediction of Henry slaw constants and aqueous solubilities for solvents and hydrocarbon fuel components. Volume 1 Technical discussion. Research Triangle Institute, National Technical Information Service Report ESL-86-86, September 1987, 86 p. 

LFL, is the lower flammable limit of fuel component i (%vol) Flammability limits can be narrowed by the addition of inert gases such as nitrogen or carbon dioxide. 

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