health and safety plan solid waste management unit assessment

AUTOMOTIVE GASOLINE 65-8
65.1 MAJOR USES AND COMPOSITION
65.1.1 Major Uses
Gasoline is a volatile mixture of flammable liquid hydrocarbons
derived chiefly from crude petroleum and used principally as a fuel for
internal combustion engines. Consumption of gasoline by motor vehicles
in this country was approximately 103 billion gallons in 1983, down
from a peak consumption of 116 billion gallons in 1978 (1409).
65.1.2 Composition
Automotive gasoline is composed of several hundred hydrocarbons in
the range of C, to C,, and with boiling points. from approximately 3G'C
to 21O'C. General composition expressed as percent weight by compound
category has been reported to be: 49% to 62% aliphatic hydrocarbons
(28-36% branched alkanes, 15-17% n-alkanes, and 3-S% cycloalkanes), 1%
to 11% olefinic hydrocarbons, 20% to 49% benzenes and alkylbenrenes and
up to to 1% naphthalenes (2320,1843,1849).
As noted with JP-4 (Chapter 64), the concentrations of specific
hydrocarbons in different gasoline samples are highly variable and are
expected r3 become even more variable as the availability of leaded
gasoline is reduced. For example, as reforming severity was adjusted
to achieve the
pools, average
required
aromatic
increase
content
in octane
increased
levels of unleaded gasoline
fro* 22% in 1970 to 27% in
1980 and 1984; as leaded gasoline is phased
will increase further to 35%. Olefin content
out,
also
the aromatic content
increased from 8% in
1980 to 11% in 1984 (2319).
The individual components of gasoline have been characterized by
several authors (2320,2311,1843). Table 65-l summarizes the available
hydrocarbon composition data for various gasolines. As discussed in
Chapter 64 (JP-4), petroleum-derived distillates may also contain many
non-hydrocarbon components. These may become major concerns in heavy
distillates and residues but are much less important in light
distillates such as automotive gasoline where only trace quantities of
sulfur-, nitrogen-, and. oxygen-containing compounds have been detected.
Large variations in trace element concentrations were reported but no
quantitative data were available (1843).
Automotive gasoline also contains a number of additives used as
octane improvers, antioxidants, metal deactivators, corrosions or icing
inhibitors, detergents or demulsifiers. A list of some of the chemical
classes and specific chemicals that may be used for these purposes is
provided in Table 65-2.
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