GASOLINE

Gasoline consists of a very large number of different hydrocarbons, and the individual hydrocarbons in gasoline cannot be conveniently used to describe gasoline. The composition of gasoline is best expressed in terms of hydrocarbon types that enable inferences to be made about the behavior in service. The volatility of a liquid is the tendency of the liquid to change from the liquid to the vapor or gaseous state. Octane numbers are obtained by two test procedures; those obtained by the first method are called motor octane numbers. Those obtained by the second method are called research octane numbers. Additives are chemical compounds intended to improve some specific properties of gasoline or other petroleum products and can be monofunctional or multifunctional. Test methods have been developed to measure ethers and alcohols in gasoline-range hydrocarbons, because oxygenated components such as methyl t-butyl ether and ethanol are common blending components in gasoline.