• Working principle‌

Extraction Column‌: The extraction column uses the difference in solubility of compounds in two immiscible solvents to transfer the target compound from one solvent to another by liquid-liquid extraction. This process relies on the distribution law, that is, the difference in solubility of substances in different solvents. ‌12
Rectification Column‌: The Rectification Column/distillation column uses the difference in volatility of each component in the mixture to separate by gas-liquid contact. The light component is enriched in the gas phase, while the heavy component is enriched in the liquid phase, thereby achieving the purpose of separation. ‌3
 

• Application scenario

‌Extraction Column‌: It is widely used in the fields of chemical industry, petroleum refining and environmental protection. It is suitable for separating compounds with similar boiling points or difficult to separate by conventional distillation. ‌1
Rectification Column‌: It is widely used in petrochemical production, mainly used to separate mixtures with large differences in boiling points to obtain high-purity products.
 

• Structural features

‌Extraction Column‌:‌: It usually adopts tower equipment, and the internal structure design allows a liquid to be broken into droplets and dispersed in another continuous liquid for extraction. This design helps to improve the extraction efficiency.
Rectification Column‌: It can be a plate tower or a packed tower, which mainly relies on the contact and mass and heat transfer process between the gas and liquid phases to achieve separation. The height and diameter of the distillation tower are usually large to provide sufficient contact area and heat transfer efficiency.