How can your lab cut water use in reflux reactions?

Condenser

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Practical advice builds on a new study comparing air-cooled condensers

If you work in a lab where you run chemical reactions under reflux conditions, you’ve likely considered the downsides of using water in your condenser. Such experiments heat a solvent to boiling, using a condenser above the reaction vessel to cool and capture the vapour produced, returning it as liquid to the vessel. Traditionally chemists cool Liebig condensers using flowing water at rates estimated at 1 to 4l/minute. This racks up large water bills, wastes a precious resource, and can lead to leaks and floods in your lab. Here’s how you can minimise or even avoid these downsides using alternative methods.