Pyrolysis of alkane is known as

In the absence of air when alkane vapors are passed through red-hot metal it breaks down into simpler hydrocarbons. This is also known as Cracking.

Eg: The pyrolysis of n-hexane takes place at 773K. The pyrolysis of n-hexane gives n-hexene, hydrogen, butene, ethane, propene,methane.,Iso-hexane ,cyclohexane etc.