Gasolines major components

Kerosene is heavier than gasoline and lighter than gas oil. The lighter portion of kerosene is most suitable as an illuminant for lamps. The heavier portions of kerosene traditionally have been used as stove oil. Since the 1950s, kerosene has been used as a major component in jet fuel. 

The data below give the vapor pressure of octane, a major component of gasoline. 

Other major components in gasoline come from catalytic reforming, alkylation and the addition of an oxygenated octane booster, methyl tertiary-butyl ether (MTB E). 

Apart from hydrocarbons and gasoline, other possible fuels include hydrazine, ammonia, and methanol, to mention just a few. Fuel cells powered by direct conversion of liquid methanol have promise as a possible alternative to batteries for portable electronic devices (cf. below). These considerations already indicate that fuel cells are not stand-alone devices, but need many supporting accessories, which consume current produced by the cell and thus lower the overall electrical efficiencies. The schematic of the major components of a so-called fuel cell system is shown in Figure 22. Fuel cell systems require sophisticated control systems to provide accurate metering of the fuel and air and to exhaust the reaction products. Important operational factors include stoichiometry of the reactants, pressure balance across the separator membrane, and freedom from impurities that shorten life (i.e., poison the catalysts). Depending on the application, a power-conditioning unit may be added to convert the direct current from the fuel cell into alternating current. 

Studies at Mobil Research have shown that light olefins instead of gasoline can be made from methanol by modifying both the ZSM-5-type MTG (Methanol-to-Gasoline) catalyst and the operating conditions. Work carried out in micro-scale fluidized-bed reactors show that methanol can be completely converted to a mixture of hydrocarbons containing about 76 wt% C2-C5 olefins. The remaining hydrocarbons are 9% C1-C5 paraffins, of which the major component is isobutane, and 15% C6+, half of which is aromatic. 

Alkylate is a gasoline blending component with exceptional antiknock properties, which seems to avoid the legislative pressure. Alkylate consists exclusively of isoalkanes and is obtained from the C3-C4 cut of the FCC units. In many instances, isobutene from the C3-C4 fraction is transformed selectively with methanol into methyl tert-butyl ether (MTBE). Therefore, a mixture of 1-butene and 2-butene is used for alkylation purposes. The other reactant is isobutane. The major constituents of the alkylate are 2,2,3-, 2,2,4-, 2,3,3- and 2,3,4-trimethyl pentane (TMP). Besides, the alkylate contains other C8 isoalkanes, such as dimethyl hexane (DMH), 3-ethyl 2-methyl pentane, methyl heptane and ethyl hexane, and even isoalkanes with carbon numbers that are not multiples of 4. 

Hexanes are a colorless, very volatile liquid with a faint, peculiar odor. It is rarely sold as n-hexane but usually admixed with hexane isomers simply called hexanes , but marketed as hexane . Hexane has a boiling point of 69 Celsius, and a melting point of-100 Celsius. It is insoluble in water, but miscible with alcohol, chloroform, and ether. Hexane is a major component of gasoline, and can be distilled from the gasoline using a multiple-path distillation apparatus. Hexane is obtained commercially from petroleum, and is a widely available commercial chemical. 

Summary Gasoline can be distilled to yield a variety of products, one of which is the desired hexanes. Hexanes are widely used as a solvent, and are a major component of gasoline. 

Isooctane (2,2,4-tri methyl pentane) is a major component of petrol (gasoline). Strictly speaking, if we follow the standard meaning for Iso (p. 29), the name isooctane should be reserved for the Isomer 2-methylheprane. However, 2,2,4-tri methyl pentane Is by far the most Important isomer of octane and so, historically, it has ended up with this name. 

Calculate the number of carbon atoms in 1.000 gallon of octane, CgHig, a major component of gasoline (1 gallon = 3.785 L density = 0.7025 g/mL). 

Alkanes are widely used as fuels Methane is familiar as natural gas, propane is used as bottled gas and as a fuel for welding torches, butane is used as cigarette lighter fluid, and octane is a major component in gasoline. 

Today, petroleum is the chief source of the enormous quantities of benzene, toluene, and the xylenes required for chemicals and fuels. Half of the toluene and xylenes are utilized in high-test gasoline where, in a sense, they replace the aliphatic compounds—inferior as fuels—from which they were made. (A considerable fraction even of naphthalene, the major component of coal tar distillate, is now being produced from petroleum hydrocarbons.)... 

Physical and Chemical Properties of Gasoline 3-3 Major Components of Gasoline a... 

The bioaccumulation potentials of the major components of gasoline range from low to high. Some higher molecular weight components (e.g., naphthalene and substituted naphthalenes) may be taken up by fish and domestic animals and bioconcentrated if they persist in environmental media (Air Force 1989). Alkenes have low log octanol/water partition coefficients (K°w) of about 1 and estimated bioconcentration factors (BCF) of about 10 aromatics have intermediate values (log K° values of 2-3 and BCF values of 20- 200), while O and greater alkanes have fairly high values (log K°w values of about 3-4.5 and BCF values of 100-1,500) (NESCAUM 1989). 

Are thermally and chemically stable, it is the major component of leaded gasolines. 

Figures 2 and 3 are photographs of the fully integrated 50 kW, ambient pressure, gasoline-fueled power plant showing the locations of major components.

---