Rotary Evaporator Lab Procedure PDF

Using the Rotary Evaporator in the Laboratory: The rotary evaporator is a laboratory device used to remove solvents at lower temperatures than their boiling points by applying reduced pressure. This process involves several key components. Components of the Rotary Evaporator Setup: 1. Hot Water Bat...

Using the Rotary Evaporator in the Laboratory: The rotary evaporator is a laboratory device used to remove solvents at lower temperatures than their boiling points by applying reduced pressure. This process involves several key components. Components of the Rotary Evaporator Setup: 1. Hot Water Bath: Heats the flask containing dissolved materials, as evaporation is an endothermic process. 2. Adapter: Connects the round bottom flask to the rotary motor, available in various sizes (e.g., 19/26 neck). 3. Rotary Motor: Rotates the round bottom flask, increasing the surface area for solvent evaporation. 4. Aspirator: Creates a vacuum through suction. 5. Condenser: Condenses vaporized solvent back into liquid. 6. Receiver: Collects the condensed solvent. 7. Chiller: Maintains low temperatures in the condenser. Procedure Step 1: Setup 1. Turn on the Main Switch: Ensure the chiller reservoir is filled with isopropanol. 2. Activate the Chiller: Set and maintain the temperature between -10°C and -15°C. 3. Prepare Aspirator: Ensure it’s filled with water. 4. Flask Preparation: The round bottom flask should be half-filled, and the stirring bar should be removed. Step 2: Initial Setup 1. Empty the Solvent Reservoir: Check that it’s empty. 2. Loosen the Clip on the Receiver: Use both hands to remove the clip and rotate the receiver out. 3. Clean the Instrument: Insert a 50 ml beaker of acetone into the mouth of the aspirator. 4. Check Chiller Temperature: Ensure it is maintained at -10°C. Step 3: Operating the Rotary Evaporator 1. Secure the Flask: Hold the round bottom flask in place with your right hand. 2. Turn on the Aspirator: Use your left hand to gently switch on the vacuum, noting the sound changes to indicate vacuum status. Blue indicator facing down = Vacuum off Blue indicator facing you = Vacuum on 3. Activate Rotation: Turn on the rotary motor and adjust the speed as desired. 4. Submerge Flask: Unlock the lever anti-clockwise using both hands, lower the setup into the water bath, then rotate clockwise to relock the lever. Step 4: Monitoring Evaporation - Observe the condenser for the flow of condensed solvent into the receiver. When no solvent remains in the flask, proceed to the next steps. Step 5: Sample Removal 1. Turn Off the Vacuum: Adjust rotation speed to the lowest setting. 2. Switch Off the Aspirator: Carefully remove the round bottom flask from the adapter. Step 6: Solid Sample Extraction - Use a flexible metal spatula to scrape the solid sample from the flask walls and transfer it to a small bag. Step 7: Liquid Sample Transfer 1. Prepare Equipment: Use a glass vial, rubber cap, and glass pipette. 2. Transfer Liquid: Insert the glass pipette into the round bottom flask and withdraw the liquid. Transfer it to the glass vial by inserting the pipette and releasing the liquid. Step 8: Clean Up - Remove the solvent from the receiver and dispose of it in the correct waste container: - Chlorinated Solvents (e.g., chloroform): Use the yellow labeled waste bottle. - Non-Chlorinated Solvents (e.g., acetone): Use the white labeled waste bottle.