Why is “liquified petroleum gas” not simply called “liquid petroleum”?
Liquified Petroleum Gas (LPG) can be one of several combinations of propane and/or butane. You could call it liquid petroleum if you want to but gasoline, lighter fluid, bar-b-que starter, white gas, fuel for a Coleman store or light all are also liquid petroleum but they have distinct names. Liquid propane or butane are called LPG or by their generic names. The term comes from the fact that most propane or butane used for home heating and cooking, portable grills, campers, etc is obtained by removing the propane or butane from natural gas. When mixed in a natural gas stream with methane, ethane, pentane and other light hydrocarbons they are also in the gaseous form. They are removed at high pressure from the natural gas, purified, and stored as a liquid; therefore they are liquified petroleum gases. At normal ambient temperatures propane must be at about 200 psi pressure to be a liquid. With butane the pressure is only 50 to 80 psi to be a liquid. The actual pressure depends on how pu
