What are the methods for separation and purification of crude oil?

Crude oil is separated and purified through **fractional distillation**, where the oil is heated, and components separate based on boiling points. Further purification includes **cracking** (breaking down larger molecules into smaller ones), **hydrotreating** (removing sulfur and nitrogen), and **desalting** (removing salts and water). These methods refine crude oil into products like gasoline, diesel, and kerosene.