What are the best tools for cooling chemical reactions?

Posted on September 3, 2024 by Cameron Fordham

Temperature control, including cooling chemical reactions, is essential across a wide range of chemical processes. Heating is generally more common than cooling, with tools such as hotplates and heating blocks or the classic school room Bunsen burner coming to mind, but that’s not to say that cooling should be overlooked as it provides many new avenues for research.

Cooling equipment has two main purposes; First is to achieve sub-ambient temperatures and second is to maintain a constant temperature when working with exothermic reactions or equipment that produces a significant amount of heat (for examples photoreactors).

Circulators are a great tool for precise temperature regulation

Examples of processes that require cooling:

NMR – nuclear magnetic resonance requires extremely low temperatures
Haber process – this process, used to produce ammonia, requires negative temperatures in order to separate the ammonia from the nitrogen and hydrogen by-products
Distillation – distillation often requires cooling for chemical separation
Condensing – heat transfer from a gas / vapour is used to condense it into a liquid. This is often achieved with water condensers, but for our waterless, sustainable alternative see here
Cryogenic gas separation – similarly to the separation of ammonia from hydrogen and nitrogen many other gas mixtures are cooled in order to be separated

What kind of equipment is used for cooling chemical reactions?

Circulators – these tools circulate a heat carrying fluid around the reaction and back into the circulator where the temperature is increased / decreased as required. They’ll often be programmable so they can be set to maintain a continuous temperature – including sub-ambient.
Jacketed vessels – Jacketed vessels feature a secondary glass jacket that surrounds the interior reaction chamber. The jackets can be connected to a circulator and used to regulate the temperature of the internal reaction. When a more extreme temperature is required a third, vacuum jacket can be added outside of the second to provide increased insulation.
Liquid nitrogen generators – liquid nitrogen is essential for many cryogenic processes: from sample storage, to being used to insulate the even colder liquid helium used in MRI machines.
Fans – Asynt’s photoreactors naturally create some heat from the LED’s when running. In order to dissipate this heat each reactor has an inbuilt fan to cool the LEDs. The Illumin8 fan can also be set to cool the reaction in addition if required as the LEDs are situated in close proximity to the reaction vials.