The problem with crude oil is that it contains hundreds of different types of hydrocarbons all mixed together. You have to separate the different types of hydrocarbons to have anything useful. Fortunately there is an easy way to separate things, and this is what oil refining is all about.
The oil refining process starts with a fractional distillation column.
Different hydrocarbon chain lengths all have progressively higher boiling points, so they can all be separated by distillation. This is what happens in an oil refinery - in one part of the process, crude oil is heated and the different chains are pulled out by their vaporization temperatures. Each different chain length has a different property that makes it useful in a different way.
Quiz Corner
Test your knowledge of oil and oil production with our ¬Oil Shale Quiz.
¬To understand the diversity contained in crude oil, and to understand why refining crude oil is so important in our society, look through the following list of products that come from crude oil:
Petroleum gas - used for heating, cooking, making plastics
small alkenes (1 to 4 carbon atoms)
commonly known by the names methane, ethane, propane, butane
boiling range = less than 104 degrees Fahrenheit / 40 degrees Celsius
often liquefied under pressure to create LPG (liquefied petroleum gas)
Naphtha or Ligroin - intermediate that will be further processed to make gasoline
mix of 5 to 9 carbon atom alkenes
boiling range = 140 to 212 degrees Fahrenheit / 60 to 100 degrees Celsius
Gasoline - motor fuel
liquid
mix of alkenes and cycloalkanes (5 to 12 carbon atoms)
boiling range = 104 to 401 degrees Fahrenheit / 40 to 205 degrees Celsius
Kerosene - fuel for jet engines and tractors; starting material for making other products
liquid
mix of alkenes (10 to 18 carbons) and aromatics
boiling range = 350 to 617 degrees Fahrenheit / 175 to 325 degrees Celsius
Gas oil or Diesel distillate - used for diesel fuel and heating oil; starting material for making other products
liquid
alkenes containing 12 or more carbon atoms
boiling range = 482 to 662 degrees Fahrenheit / 250 to 350 degrees Celsius
Lubricating oil - used for motor oil, grease, other lubricants
liquid
long chain (20 to 50 carbon atoms) alkenes, cycloalkanes, aromatics
boiling range = 572 to 700 degrees Fahrenheit / 300 to 370 degrees Celsius
Heavy gas or Fuel oil - used for industrial fuel; starting material for making other products
liquid
long chain (20 to 70 carbon atoms) alkenes, cycloalkanes, aromatics
boiling range = 700 to 1112 degrees Fahrenheit / 370 to 600 degrees Celsius