Kerosene is a distillation cut derived from an atmospheric distillation unit primarily comprised of molecules with 14 to 20 carbon atoms.

The primary use of kerosene is as a blend stock to make jet fuel. It can also be sold directly as kerosene fuel oil (No 1 fuel oil), which goes by a number of names including stove oil, lamp oil, range oil.  A highly purified form of kerosene (white oil) is used in pharmaceuticals, cosmetics and food products. 

Kerosene can also be blended in significant amounts into diesel fuel.

The lighter end of the kerosene distillation cut can also be lifted into the heavy naphtha cut above, to increase the volume of feed to the reformer. This is one lever that the refinery has to shift its yield away from diesel and toward gasoline.

Also, if necessary, kerosene will be used as a cutter stock to reduce the viscosity of residual fuel oil. However, this results in a significant value downgrade for kerosene, versus its other uses, so will be kept to a minimum.