Exercise 15: Reading: Major refinery productsGasoline. The most important refinery product is motor gasoline, a blend of hydrocarbons with boiling rangesfrom ambient temperature to about 200oC. The important qualities for gasoline are octane number (antiknock),volatility (starting and vapor lock), and vapor pressure (environmental control). Additives are often used toenhance performance and provide protection against oxidation and rust formation.Kerosene. Kerosene is a refined middle-distillate petroleum product that finds considerable use as a jet fuel andaround the world in cooking and space heating. When used as a jet fuel, some of the critical qualities are freezepoint, flash point, and smoke point. Commercial jet fuel has a boiling range of about 190-280oC and military jetfuel 55-290oC. Kerosene, with less-critical specifications, is used for lighting, heating, solvents, and blending intodiesel fuel.Liquefied petroleum gas (LPG). LPG, which consists principally of propane and butane, is produced for use asfuel and is an intermediate material in the manufacture of petrochemicals. The important specifications forproper performance include vapor pressure and control of contaminants.Distillate fuels. Diesel fuels and domestic heating oils have boiling ranges of about 200-370oC. The desirablequalities required for distillate fuels include controlled flash point and pour point, clean burning, no depositformation in storage tanks, and a proper diesel fuel cetane rating for good starting and combustion.
Residual fuels. Many marine vessels, power plants, commercial buildings and industrial facilities use residual
fuels or combinations of residual and distillate fuels for heating and processing. The two most critical
specifications of residual fuels are viscosity and low sulfur content for environmental control.
Coke and asphalt. Coke is almost pure carbon with a variety of uses from electrodes to charcoal briquets.
Asphalt, used for roads and roofing materials, must be inert to most chemicals and weather conditions.
Solvents. A variety of products, whose boiling points and hydrocarbon composition are closely controlled, are
produced for use as solvents. These include benzene, toluene, and xylene.
Petrochemicals. Many products derived from crude oil refining, such as ethylene, propylene,butylenes, and
isobutylene, are primarily intended for use as petrochemical feedstock in the production of plastics, synthetic
fibers, synthetic rubbers, and other products.
Lubricants. Special refining processes produce lubricating oil base stocks. Additives such as demulsifiers,
antioxidants, and viscosity improvers are blended into the base stocks to provide the characteristics required
for motor oils, industrial greases, lubricants, and cutting oils. The most critical quality for lubricating oil base
stock is a high viscosity index, which provides for greater consistency under varying temperatures.
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