environments. Historically, early exposures resulted from the use of woodburning fires and then from using coal for domestic heating. Combustion of
fossil fuel associated with developing industry, explosions, fires in mines, and
illumination gas prepared from coal all have been sources of exposure. The
migration of agricultural populations to cities increased the proportion of
exposed population, as well as the number of persons generating CO. With the
emergence of automobiles propelled by internal combustion engines, CO
emitted from exhaust pipes has become the major source for human exposure.
Serious problems also exist due to occupational exposure to increased levels of
CO.
8.5.2 FORMATION
Carbon monoxide is usually formed through one of the following three
processes: incomplete combustion of carbon-containing fuels, reactions
between CO 2 and carbon-containing materials at high temperature, and
dissociation of CO 2 at high temperatures.
Incomplete combustion of carbon or carbon-containing compounds occurs
when the available oxygen is less than the amount required for complete
combustion, in which CO 2 would be the product (Reaction 8.21 and Reaction
8.22). It will also occur when there is poor mixing of fuel and air.
2C þ O 2 ! 2CO
ð8:21Þ
2CO þ O 2 ! 2CO 2
ð8:22Þ
Carbon monoxide is also produced when CO 2 reacts with carbon-containing materials at an elevated temperature (Reaction 8.23). Such reactions are
common in many industrial devices.
CO 2 þ C ! 2CO
ð8:23Þ
The CO produced in this way is utilized in a variety of industrial facilities,
such as the blast furnace of a smelter, where the CO acts as a reducing agent in
the production of iron from Fe 2 O 3 ores (Reaction 8.24). Some CO may,
however, escape into the atmosphere.
3CO þ Fe 2 O 3 ! 2Fe þ 3CO 2
ð8:24Þ
CO may also be produced by the dissociation of carbon dioxide into CO
and O at high temperatures, as shown in Reaction 8.25.
ð8:25Þ
128
Environmental Toxicology
[16:53 26/8/04 P:/CRC PRESS/4365 MING-HO.751 (1670)/4365-008.3d]
Ref: 4365 MING-HO YU Chap-008 Page: 128 111-134
fossil fuel associated with developing industry, explosions, fires in mines, and
illumination gas prepared from coal all have been sources of exposure. The
migration of agricultural populations to cities increased the proportion of
exposed population, as well as the number of persons generating CO. With the
emergence of automobiles propelled by internal combustion engines, CO
emitted from exhaust pipes has become the major source for human exposure.
Serious problems also exist due to occupational exposure to increased levels of
CO.
8.5.2 FORMATION
Carbon monoxide is usually formed through one of the following three
processes: incomplete combustion of carbon-containing fuels, reactions
between CO 2 and carbon-containing materials at high temperature, and
dissociation of CO 2 at high temperatures.
Incomplete combustion of carbon or carbon-containing compounds occurs
when the available oxygen is less than the amount required for complete
combustion, in which CO 2 would be the product (Reaction 8.21 and Reaction
8.22). It will also occur when there is poor mixing of fuel and air.
2C þ O 2 ! 2CO
ð8:21Þ
2CO þ O 2 ! 2CO 2
ð8:22Þ
Carbon monoxide is also produced when CO 2 reacts with carbon-containing materials at an elevated temperature (Reaction 8.23). Such reactions are
common in many industrial devices.
CO 2 þ C ! 2CO
ð8:23Þ
The CO produced in this way is utilized in a variety of industrial facilities,
such as the blast furnace of a smelter, where the CO acts as a reducing agent in
the production of iron from Fe 2 O 3 ores (Reaction 8.24). Some CO may,
however, escape into the atmosphere.
3CO þ Fe 2 O 3 ! 2Fe þ 3CO 2
ð8:24Þ
CO may also be produced by the dissociation of carbon dioxide into CO
and O at high temperatures, as shown in Reaction 8.25.
ð8:25Þ
128
Environmental Toxicology
[16:53 26/8/04 P:/CRC PRESS/4365 MING-HO.751 (1670)/4365-008.3d]
Ref: 4365 MING-HO YU Chap-008 Page: 128 111-134