What is the function of a distillation column?

The function of a distillation column is to separate crude oil into fractions. In the context of refining, crude oil is composed of a diverse mixture of hydrocarbons, each with varying boiling points. The distillation column utilizes the principle of thermal separation, where heat is applied to vaporize the crude oil. As the vapor rises through the column, it cools and condenses at different heights where various fractions can be collected. This process enables the separation of lighter fractions, such as gases and gasoline, from heavier fractions like diesel and lubricating oils.

The other options do not accurately describe the primary purpose of a distillation column. Mixing different oil types, for example, occurs downstream of the distillation process and does not rely on the principles of fractional separation. Breaking down large molecules is typically associated with processes like cracking, rather than distillation. Storing finished petroleum products is functionally different from the role of a distillation column, which focuses specifically on the separation of components within crude oil rather than storage.