How to Use a Rotovap #Science

Summary

In this video, the process of using a rotary evaporator (rotovap) is explained. The rotovap is a lab tool designed to remove solvents by reducing pressure, increasing surface area through rotation, and applying heat. The procedure includes setting up the water bath and vacuum, placing the solution into the system, initiating rotation, and managing heat. After the process, proper removal of the flask and solvent disposal are emphasized. This concise guide ensures safe and effective operation of the rotovap for solvent recovery.

Takeaways

• 😀 Turn on the cold water gently before starting the rotary evaporator.
• 😀 Close the stopcock at the top of the condenser to secure it in place.
• 😀 Place and hold the splash trap in position as there is no other support.
• 😀 Insert the round bottom flask containing your solution into the rotovap.
• 😀 Start the vacuum system and wait until it reaches -10 pressure before proceeding.
• 😀 Begin rotating the round bottom flask once the vacuum reaches -10 pressure.
• 😀 Avoid delays in starting the rotation to prevent bumping and losing solution into the splash trap.
• 😀 Lower the round bottom flask into the hot water bath to facilitate evaporation.
• 😀 For low boiling point solvents, the water bath heat may not be necessary.
• 😀 After the solvent has evaporated, carefully remove the round bottom flask from the rotovap.
• 😀 Release the stopcock, turn off the vacuum, and remove the round bottom flask with care.
• 😀 Properly dispose of any residual solvent in the receiving flask following waste disposal guidelines.
• 😀 Always turn off the cold water supply after completing the rotovap process.

Q & A

What is the main purpose of using a rotary evaporator (rotovap)?

The main purpose of using a rotary evaporator is to remove a solvent from a solution by reducing the pressure inside the round bottom flask, increasing the surface area through rotation, and optionally heating the solvent.

Why is it important to turn on the cold water before using the rotovap?

Turning on the cold water helps cool the condenser, which is essential for condensing the evaporated solvent and ensuring that it can be collected properly.

What role does the stopcock at the top of the condenser play in the process?

The stopcock controls the flow of gases and pressure in the system. It should be closed gently before starting the process to ensure proper vacuum creation.

What is the purpose of the splash trap in the rotovap setup?

The splash trap is used to prevent any solvent or liquid from splashing out of the system during the evaporation process. It must be held in place as there is nothing securing it initially.

Why is it crucial to start the rotation after the vacuum reaches -10 mbar?

Starting the rotation after reaching -10 mbar ensures that the solution does not bump into the splash trap, which could lead to loss of the solution.

What happens if you wait too long to start the rotation after the vacuum is applied?

If the rotation is started too late, there is a risk of the solution bumping into the splash trap, potentially leading to spillage and loss of material.

Is it necessary to apply heat during the solvent removal process?

For solvents with a low boiling point, applying heat may not be necessary. However, for higher boiling point solvents, the use of heat in the water bath can speed up the evaporation process.

How should the round bottom flask be handled after the solvent is removed?

After the solvent is removed, carefully remove the round bottom flask from the rotovap, release the stopcock, turn off the vacuum, and safely place the flask in a beaker.

What should be done with the solvent collected in the receiving flask?

The solvent collected in the receiving flask should be disposed of properly, in accordance with safety protocols, in the correct waste disposal containers.

What are the final steps after using the rotovap?

After using the rotovap, ensure to turn off the water supply to the condenser and dispose of the solvent correctly. Always make sure the system is cleaned and shut down properly.