In oil refining, what is meant by 'cracking'?

In oil refining, 'cracking' refers specifically to the technique of breaking down larger hydrocarbon molecules into smaller, more useful products. Through this process, heavy fractions of crude oil are transformed into lighter and more valuable products such as gasoline, diesel, and kerosene. Cracking typically involves the application of heat, pressure, and sometimes the use of catalysts to facilitate the breaking of carbon-carbon bonds within the hydrocarbon chains.

This method is crucial for maximizing the yield of valuable fuels from crude oil, as not all components of crude oil are inherently useful or desirable in their original form. By cracking the heavier hydrocarbons, refineries can adjust the output to meet market demands for various types of fuels and chemicals, thus improving overall efficiency and profitability in oil refining operations.

Other methods, such as filtration, color enhancement, or mixing processes, do not relate to the core concept of chemical breakdown of hydrocarbons, which is central to cracking.