Chemistry Reference
In-Depth Information
All steel used to be made by treating iron ore (iron oxides) with carbon.
In colonial days, the required carbon (charcoal) was obtained by the heating
of wood in the absence of air. The wood was ultimately replaced by coal.
To obtain carbon (coke) from coal, the coal was heated to about 2500°F.
Gaseous and liquid organics distilled from the coking operation. The gaseous
fraction (coal gas) was used for street-lighting in large towns. The high-
boiling material (coal tar) was used for roofing and road building. The liquid
(coal oil) was about two-thirds benzene along with higher aromatics. All of
the benzene used before World War II came from this source. Now, none of
it does.
Naphtha is a mixture of aliphatic hydrocarbons isolated from petroleum
by distillation. When it is passed over a catalyst under the right conditions,
carbon rings are formed, followed by the splitting of hydrogen from the
carbon rings to produce benzene, toluene, and other aromatic compounds.
