Setting up a distillation for the first time can seem to be quite a puzzle: just how do all these pieces of glassware go together? Where should you start? Where does the water go in? The following sections on distillation set-up should help ease you into your first laboratory distillation experience. Go through the photos below before your first distillation, and again as needed.
The Process of Set-up
The following series of photos illustrate the different steps in a simple distillation set-up. This is one good way to set up a distillation. If you observed seasoned organic chemists in the lab, they would each set it up in a slightly different manner. This series of steps is designed for the beginning distiller, to get you started in a logical and safe manner.
|Begin with a round-bottom flask. This is one of the most critical pieces of glassware in the assembly, since it will hold the liquid to be distilled. You don't want it to fall and break because you would lose your compound and possibly spill a hazardous chemical. To secure your setup, you will need a small three-pronged clamp, two ring stands, and a ring clamp.|
|Place the ring clamp and three-pronged clamp on the ring stand. The ring clamp goes on the bottom and will hold the heat source, either a steam bath (no longer used in the organic labs) or a heating mantle. Secure the round-bottom flask to the ring stand using the three-pronged clamp. The next item to be added is the Y-adaptor.|
|The Y-adaptor sits on top of the round-bottom flask. The next item to be added, the condenser , will secure the Y-adaptor to the system. You will also need a Keck clip and a versatile clamp.|
|Connect the condenser to the Y-adaptor and secure the connection with a Keck clip. Secure the condenser to the ring stand with a versatile clamp. The next items you will need are a vacuum adaptor and another Keck clip.|
|Connect the vacuum adaptor to the condenser and secure the connection with a Keck clip. Add a couple of boiling chips to the round-bottom flask by dropping them down through the Y-adaptor.|
|Place a stemmed funnel into the top of the Y-adaptor and pour the liquid to be distilled through it so that it goes into the round bottom flask. The flask should be between 1/2 full and 2/3 full. When done, remove the funnel.|
|This picture is only different from the last in that an Erlenmeyer flask has been placed under the vacuum adaptor. This is the receiving flask. A beaker, vial or graduated cylinder could also be used. In a vacuum distillation, a round bottom flask is used as the receiving flask, and it is securely attached with either a clamp or a yellow clip. The next items to be added are the thermometer adaptor and thermometer. The thermometer is always added last because it is large and susceptible to breakeage.|
|Here is all the glassware properly assembled. The thermometer and thermometer adaptor are connected on top of the Y-adaptor. Note the correct placement of the thermometer - this is vital for correct measurement of boiling point. The collection flask has been temporarily removed to protect it during the addition of the heat source, which could cause an unsecured flask to fall and break.|
|Collect two pieces of Tygon tubing for the condenser. If you are using a steam bath for the heat source, you will need four lengths.|
|Place the heat source on the ring under the round-bottom flask. Adjust the height of the apparatus as necessary. Connect two pieces of Tygon tubing to the condenser. The tubing to the lower connection goes to the water source, the upper connection goes to the drain. Remember, in through the bottom, out through the top. If you are using a steam bath, connect it to two pieces of Tygon tubing: one to the lower and one to the upper connection. The tubing at the upper connection goes to the steam source, the lower one goes to the drain. Make sure all of the glass and tubing joints are tight before turning on the cooling water and the steam. Begin heating the round-bottom flask carefully.|
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