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Reading Selection, Lesson 7

Boiling Oil

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Historic photo of a Texas oil well gushing oil

This old Texas gusher shows crude oil, under pressure from surrounding gas, being forced up from under the ground. Once out of the ground, the oil must be processed.

The next time you visit a gas station, look at some of the products sold there. In addition to gasoline, you'll probably find diesel fuel, kerosene, engine oil, gear grease, and other lubricants. All of these substances help keep cars and other vehicles running. Where do they come from?

A car's ability to cruise down the highway—and possibly even the highway itself' is based on the activity of a variety of organisms that lived in the sea hundreds of millions of years ago. These organisms died, but they only partially decomposed. Over millions of years, their remains became compressed, were heated, and eventually turned into crude oil and natural gas. By drilling down into the rocks where the crude oil and gas are found, it is possible to extract it.

Many oils (or tractions) all obtained from the fractional distillation process.

All of these different oils (or fractions) were obtained from crude oil by the process of fractional distillation. Each fraction has a different boiling point.

Crude oil is very thick, comes in a variety of unusual colors (including red), and smells pretty awful. How is crude oil made into substances that can be used in cars? When crude oil is boiled, a lot of interesting things happen. You see, crude oil is not a single substance. It's a mixture.

As crude oil is heated, some of the substances in it start to boil. Substances with low boiling points, like gasoline, are the first to boil. Kerosene is next, followed by fuel oils (some of which are used to make diesel fuel) and then heavier oils (which are often used for lubrication). In the end, only the substances with high boiling points (more than 370 °C) are left—as a dark, gooey, smelly mess. But even these materials have a use. They make up asphalt, which is used as a surface for the highways on which cars travel!

oil platform at sea

Oil is a very valuable resource, and people go to great lengths to extract it.

All this boiling takes place at an oil refinery. The crude oil is heated in special towers called fractionating towers or columns. In different levels of the towers, gases produced when the crude oil is heated are condensed. The substances that come from crude oil are not only used to make fuels and lubricants. They are also used as raw materials for hundreds of industrial processes—from making glues to plastic bottles and even clothing.





Illustration of an oil fractioning column and the products it produces.

Inside a fractioning column


Illustration of man working on van engine and children playing with a toy car and ball nearby.

How many objects in this picture could be made from oil?

Examine this picture. How many of the items in it, including car parts, could be made from oil?

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