List major commercial sources of alkanes.

Alkanes are primarily obtained from the following commercial sources:

Natural Gas: A major source of methane and other alkanes.

Petroleum: Through the distillation process, crude oil is separated into various fractions, including alkanes such as ethane, propane, butane, and others.

Coal: Alkanes are also obtained by destructive distillation of coal, which produces various gases, including methane.

Biomass: Alkanes can also be produced from the fermentation of organic matter, such as in the production of biogas.