Doupati Dheeraj
Fractional distillisation
fractional distillation
Sathvik Vatti
It is refined by chemical process changing crude oil into petrol,deseil etc

Petroleum refining processes are the chemical engineering processes and other facilities used in petroleum refineries (also referred to as oil refineries) to transform crude oil into useful products such as liquefied petroleum gas (LPG), gasoline or petrol, kerosene, jet fuel, diesel oil and fuel oils. Petroleum refineries are very large industrial complexes that involve many different processing units and auxiliary facilities such as utility units and storage tanks. Each refinery has its own unique arrangement and combination of refining processes largely determined by the refinery location, desired products, and economic considerations.

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Kiran Sangha
Adding on to Krishna's answer, petroleum is refined using petroleum refining processes (shown in the image above). As shown in the diagram, crude oil goes through various processes like a desalter, air-cooled condenser, fired heater, and a crude oil distillation tower. When processed, crude oil can be converted to end-products like liquid petroleum gas, kerosene, and wax. Image source: