Rotary Evaporators

Rotary Evaporator Systems - Your Guide

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These are the best-in-class solvent recovery products.

We only carry the top rotary evaporator brands in the industry. These products are a clear example of “you get what you pay for”. Poorly made units are more likely to malfunction, spelling potential disaster for your laboratory and your bottom line.

Price Match Assurance.

We sell only tried-and-true, industry-proven products, and all of these units are covered by our Price Match Assurance. At Lab Society, you can shop confidently, knowing that you’ve found the best quality and prices on the web.

We’ve selected only the most reliable products from brands like Heidolph and Across International, to suit every budget and desired capacity. Rest assured that each product we sell has withstood rigorous testing in real-world laboratory situations.

Let’s take a look at some of the most common types, and go into detail about how to use these important products!

Intelligent technology is at the heart of solvent recovery.

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Newer units come with easy-to-read, multi-function displays, giving you unprecedented control over every aspect of your rotovap’s function, including temperature, rotation speed, timing, and much more.

The top-of-the-line units, in particular, are more automatable and powerful than ever before.

Which rotovap should I choose?

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While each system is designed to distill, separate, and purify liquids, the key differentiators between the various products we carry are volume and output.

The images you see here may not do justice to the actual scale of these machines. Industrial evaporators like the Heidolph HBX are truly massive – more than able to meet the ongoing needs of even the most demanding laboratory applications.

Our smallest evaporation unit, on the other hand, comes in at a 2 Liter capacity – perfect for newer labs and people just getting started.

These products cover everything from light-weight cooking/culinary applications to heavy-duty solvent recovery on an industrial scale.

How does a rotary evaporator work?

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In the diagram above, you can see some of the components that make up your typical rotary evaporator. While the specific layout and functionality may change from product to product, the general concept does not.

• A water bath (or other liquid) is heated.
• A rotary flask (containing both solvent and sample combined) is lowered into the bath and partially submerged. (Note: We recommend borosilicate glass for its ability to withstand both extreme temperatures and solvents)
• Pressure is reduced in the air-tight system via a vacuum. This also prevents volatile vapors from escaping into the air and creating a potentially hazardous situation.
• A motor rotates the flask at a set speed, while precisely regulating the temperature of the bath.
• The temperature of the bath is set just high enough to evaporate the solvent, while leaving behind the sample. (Note: The water bath prevents the sample from burning/combusting during this process!)
• The heated solvent vaporizes and travels upwards through the glass and into the condenser.
• The condenser has a self-contained, chilled fluid running through it in a spiral pattern, maximizing surface area. The cooling occurs via a connected chiller.
• When the heated solvent vapors come into contact with the cooled glass of the condenser, they condense, returning to liquid form.
• Gravity once again takes hold of the pure, condensed solvent, dripping it into the collecting flask (or receiving flask).
• The sample is left behind in the rotary flask, and the pure solvent has now been separated into the receiving flask. In most cases, the solvent is so pure that it can be re-used several times!

While a similar effect could theoretically be achieved with a non-rotating piece of distillation glassware, both friction and gravity (coupled with the centrifugal force of the rotation of the flask) create a thin layer of the sample, evenly coating the glass. This increases the surface area of the sample, speeding up the evaporation process tremendously!

Uses and functionality of rotary evaporation:

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The rotary evaporation process ensures that the sample receives an even, consistent heating from the warm liquid. This, in turn, creates a smoother distribution of the sample and a more uniform temperature without overheating.

Thanks to digital temperature control, you can repeat your results with stunning accuracy, eliminating guesswork.

A wide range of industries make heavy use of these rapid-evaporation machines, including medicine, molecular gastronomy, organic chemistry, and they are ideal for making highly pure extracts.

You can now concentrate, capture, and infuse samples with a degree of accuracy never before thought possible.

Why do rotary evaporators need vacuums?

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As we mentioned, these systems operate using a vacuum, like many of the short path distillation systems we carry.

The effect of introducing a vacuum into these systems is that it reduces the boiling point of liquids and samples within the system.

This means that liquid solvents can be extracted without resorting to extreme heat, which could adversely affect both your sample and resultant condensates.

When performing evaporation on a commercial scale (or in production quantities rather than simply for analysis), these machines are preferred over smaller evaporating dishes or evaporating flasks.

Not only are they significantly faster than open-air evaporating methods, but the introduction of a vacuum to the system also prevents unwanted reactions with the atmosphere and can help contain noxious/hazardous fumes in your lab.

Using a vacuum pump also helps you mitigate violent ebullition or bumping, which is an undesirable scenario that occurs when your sample overheats too rapidly. The built-in computer controllers can further regulate the system, detecting potential errors before they become troublesome in most cases.

How much vacuum do I need?

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The specific vacuum requirements that you’ll have will change depending on which solvent you are using and its evaporating temperature. Vacuum depth is one of the many variables that is regulated in a modern system, and the needed pressure can vary greatly depending on your desired results.

Achieving the optimal pressure within the system will dramatically shorten your process times, increasing efficiency. As an added bonus, it will also reduce laboratory and environmental air pollution.

For more information about vacuums, see our in-depth Vacuum Pump Buyer’s Guide!

Handy tips:

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• If using water in the rotary evaporator’s heated bath, make sure to replace the water regularly. Also, only use distilled water and make sure that no residue or bacteria build up in the tank. 
• Make sure your glass pieces are properly connected, for example using a high-quality keck clip to keep them in place.
• Don’t overfill your glassware or water bath – always operate within the volumetric guidelines of each kit or product.
• Always properly grease your glass joints using high vacuum grease (if necessary), so your joints and glassware don’t get frozen or fused together.
• When in doubt, consult the manual!

Technical support:

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Ordering large, industrial scale rotovap systems can be a daunting task for some labs. That’s why we offer world-class support and training to get you set up with the equipment as quickly as possible.

We want to be sure that your laboratory has all the information, support, and set-up it needs to get up and running right away, saving you valuable time. With this complicated equipment, we know that you don’t need someone to sell it to you only to leave you hanging.

We’ve sold these systems around the world, and we have many years of experience in running and maintaining these very important systems.

We’ll still be there after your purchase.

For us, the relationship continues long after purchase. We want you to get the most you possibly can out of your laboratory, so we offer industry-leading support on all of our rotary evaporation (rotavap) products.

To find out exactly how we will help you use and install these precise products – before and after purchase – please give us a call!

A note about safety:

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The quality of your laboratory glassware is paramount when working with volatile compounds and potentially hazardous fumes. While a proper vacuum and seal can prevent most issues, you need to take extra care to ensure that there are no cracks or flaws in your glass.

We only sell top quality, American-made borosilicate glass for just this reason. Cheap or cracked glass could lead to implosions when heated or exposed to vacuum. At best, this can destroy your sample. At worst, it can destroy your equipment and cause serious harm to those operating it.

Always exercise proper caution when running rotary evaporators, and never leave them unattended!