Butane is one of the hydrocarbons that's easier to extract from natural gas liquids than from crude. You'll know butane as the liquid substance inside Bic lighters. It works
perfectly for cigarette lighters because it's easy to contain, and changes from liquid to gaseous form quickly.
A form of butane with the same number of atoms arranged in a different molecular structure called isobutene can be used for refrigeration, in freezers, or as a dissolved gas that
helps propel substances out of aerosol cans.