Question

What do you understand by the term of petroleum fraction?

Answer 1

Petroleum distillation is the separation  of the component parts, or fractions, of petroleum according to boiling point.
Fractionation, which performed in oil refineries, is the initial step in the refining of petroleum and in the production of petroleum products. The process is based on petroleum's capacity to be heated to a vapor phase that differs in compositions from the liquid phase. The fraction that are obtained are usually mixtures of hydrocarbons. Various individual hydrocarbons can be separated by repeated fractional distillation.
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