Clamps! Or a Clamp-like Device

This week we distilled ethanol from the fermented rice/corn/potato mash that we prepared the week before. The main challenge in distillations is the complex set up involving many pieces of glassware and apparatus. Clamping glassware and various objects to a ring stand or ring stands can be quite and ordeal. The first issue is: 1) how many clamps? The second issue is: 2) where should they go? We used a distillation apparatus with a Bunsen burner hear source. A 500 mL round-bottom flask was supported by and iron ring with a wire mesh flame spreader. The round bottom neck was held by a clamp to the ring stand. On top of the round bottom (14/20 joint) was a three way adapter and a thermometer adapter. The top of the three-way adapter was also clamped to the ring stand. The distillation condenser was attached with a Keck clip to the three way adapter. The end of the condenser was close to the opening of a 50 mL graduated cylinder. It would be great to have a second ring stand with a clamp on the condenser but alas, that is a lot of ring stands. We do not have enough curved (vacuum) adapters left because they often fall off and break if not securely clamped. I have had good success with the blue Keck clips to help hold things together if they are not used where a secure metal clamp should be used. I have learned the hard way not to put a Keck clip on a round bottom flask that is being heated with a Bunsen burner! There is a method to putting on clamps the two screws near the ring stand should be loose while the “hands” of the clamp are being tightened down. When the “hands” are secure then adjust the length and height before tightening the two screws next to the ringstand. (image source <;)


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