Crude oil is a mixture of many thousands of molecules, each with particular physical and chemical properties. Hundreds of products are made by separating and sorting these molecules, then re-combining or further processing them.
The range of products varies according to the particular type of crude oil and the refinery design. On average, processing light crude oil in modern refinery yields the following range of products:
Light fuel oil
Heavy fuel oil
Aviation jet fuel
Light crude oil contains many small, hydrogen-rich hydrocarbon molecules. It flows easily through wells and pipelines. When light oil is refined, it produces a large quantity of transportation fuels such as gasoline, diesel and jet fuel. Light oil commands the highest price per barrel.
Heavy crude oil contains many large, carbon-rich hydrocarbon molecules. Additional pumping is needed to make heavy oil flow through wells and pipelines. Heavy crude oil contains a smaller proportion of natural gasoline and diesel fuel components and requires much more extensive refining to make transportation fuels. Heavy oil commands a lower price and the difference in price per barrel is called the differential.
Synthetic crude oil is a hydrocarbon liquid produced by upgrading conventional heavy oil or bitumen extracted from oil sands. The mixture consists of hydrocarbons derived from heavy crude oil or bitumen through the addition of hydrogen and/or the removal of carbon. Synthetic crude oil sells at a premium price compared to most other crude oils.