A 20-liter rotary evaporator refers to a larger-sized laboratory equipment used for evaporation and concentration of solvents. Similar to the 10-liter rotary evaporator, the “20-liter” designation refers to the capacity of the evaporation flask, which can hold up to 20 liters of liquid.

The basic components and principles of operation of a 20-liter rotary evaporator are similar to those of a 10-liter model. Here’s a brief overview:

Evaporation Flask: The primary vessel where the sample and solvent mixture is placed. In the case of a 20-liter rotary evaporator, the flask has a capacity of 20 liters, allowing for larger sample volumes.

Heating Bath: The heating bath provides controlled heating to the flask, enabling the solvent to evaporate at a specific temperature. The bath is typically filled with a heat transfer fluid like water or oil and is heated externally.

Rotating Evaporating Flask: The evaporation flask is connected to a rotating mechanism that continuously rotates the flask. This rotation increases the surface area available for evaporation, facilitating faster and more efficient solvent removal.

Condenser: The condenser cools the evaporated solvent vapor, causing it to condense back into a liquid state. The condenser is typically cooled using a separate cooling system, such as a water bath or a chiller.

Vacuum System: A vacuum pump creates a reduced-pressure environment inside the system, which lowers the boiling point of the solvent. This reduced pressure accelerates the evaporation process and helps prevent sample degradation.

Collection Flask: The condensed solvent is collected in a separate flask for further analysis or disposal.

A 20-liter rotary evaporator is particularly useful when working with larger sample volumes or when higher evaporation rates are required. It provides a larger capacity and potentially faster evaporation compared to smaller-sized models.

Keep in mind that the specific design, features, and operation of a 20-liter rotary evaporator can vary among manufacturers and models. It’s important to consult the manufacturer’s instructions and guidelines for proper usage, safety precautions, and maintenance procedures.