The most important one is gasoline. Some other petroleum products are diesel fuel, heating oil, and jet fuel. Refineries use many different methods to make these products. One method is a heating process called distillation . Since oil products have different boiling points, the end products can be distilled or separated.
Asphalts have a higher boiling point than gasolines, allowing the two to be separated.
Refineries have another job. They remove contaminants from the oil. A refinery removes sulfur from gasoline, for example, to increase its efficiency and to reduce air pollution. Nine percent of the energy in the crude oil is used to operate the refineries. After processing at the refinery, gasoline and other petroleum products are usually shipped out through pipelines.