Rotovap Ultimate Guide for Chemistry Laboratories

Lyman C. Craig USA Chemist invented the rotary evaporation system in 1950, he could not have imagined what an innovation he had created. More than 70 years later, rotary evaporators are still responding to the needs of scientists around the world and can be found in most modern chemistry laboratories.

Due to the broad range of condensers, ‘rotovaps’ are used for fast distillation of mixed solvents, the efficient drying of samples, the quicker freeze-drying sample preparation, the chemical synthesis under reflux, the extraction of natural compounds and concentration.

Evaporation is a common step in many research and development applications. The concentration of solutions by distilling the solvent and getting rid of low and higher-boiling or solid residue is a necessary step in organic synthesis and extracting inorganic pollutants. Evaporators are also used outside research laboratories in the chemical, pharma, petrochemical and food industries.

How does a Rotary Evaporator work?

The main components of a rotary evaporator include a motor unit, a vapor duct, a vacuum system, a heated fluid bath, a condenser with either a coil passing coolant, or a ‘cold finger’, a condensate-collecting flask and a mechanical or motorized mechanism. In a rotary evaporator, the motor rotates the evaporation flask or vial containing the user’s sample. Vapor duct is the axis for sample rotation, and is a vacuum-tight conduit for the vapor being drawn off the sample.

The vacuum system substantially reduces the pressure within the evaporator system. The system can be as simple as a water aspirator with a trap immersed in a cold bath for non-toxic solvents, or as complex as a regulated mechanical vacuum pump with refrigerated trap. A heated fluid bath, which is usually water, heats the sample. The condenser used in rotary evaporator can be simple or complex, depending upon the goals of the evaporation, and any propensities the dissolved compounds might give to the mixture. The condensate-collecting flask is located at the bottom of the condenser and catches the distilling solvent after it re-condenses. The motorized mechanism quickly lifts the evaporation flask from the heating bath.

The Importance of Proper Vacuum for Rotary Evaporation

Using a vacuum source with your rotary evaporators comes with a significant set of advantages, like making your processes safer, more efficient, cleaner, and overall, easier. In this blog post, we’re going through all the reasons why owning a rotary evaporator is typically paired with using a vacuum source (either built-in or a vacuum pump).

Depending on the rotary evaporator you’re using, you might already have a built-in vacuum controller and you’ll only need to add a vacuum pump.

Controllable vacuum sources allow you to adjust the pressure with surgical precision, providing you with the desired evaporation rate.

An increase in evaporation rate can therefore be achieved without having to upscale your bath’s temperature, which will allow you to achieve evaporation rates previously unattainable using a bath alone. Using a vacuum source also leads to improved solvent-product separation thanks to the controlled and even evaporation rate. It also decreases the risk of bumping (the formation of bubbles due to hasty boiling of samples; This can lead to your sample splashing out of the flask.). 

Safety precautions

Although evaporation is a simple operation, there are hazards associated with it including implosions resulting from use of glassware that contains flaws, and explosions that may occur from concentrating unstable impurities during evaporation. Take precautions to avoid contact with rotating parts, particularly entanglement of loose clothing, hair or necklaces.

Rotary Evaporator applications:

Rotary evaporators are a versatile piece of equipment with a wide range of industrial applications. They are used in a variety of industries, including:

Crude oil processing: Rotary evaporators are used to remove solvents from crude oil, which helps to separate the different components of the oil. This can be used to improve the quality of the oil or to produce specific products from the oil.

Cannabinoid separation: Rotary evaporators are used to separate cannabinoids from plant material. This is a critical step in the production of cannabis products, such as CBD oil and THC oil.

Molecular cooking: Rotary evaporators are used in molecular cooking to create complex flavors and textures. By evaporating solvents under vacuum, the flavors and aromas of ingredients are concentrated, creating dishes that are both delicious and visually appealing.

Winemaking: Rotary evaporators are used in winemaking to remove water from grape juice. This helps to concentrate the flavors of the wine and to make it more stable.

Flavor and fragrance creation: Rotary evaporators are used in the creation of flavors and fragrances. By evaporating solvents under vacuum, the volatile compounds that give flavors and fragrances their characteristic aromas are concentrated.

Rotary evaporators manufactured by Across International meet the needs of a wide range of sectors, whether you operate in research and development or production.

Academia: Solvent re-use plays an important role in Academia. The rotary evaporator is the best choice for this and many other applications: Concentration, Solvent recycling, Distillation.

Chemical: In the chemical industry a wide range of applications can be performed with an industrial Rotavapor: Concentration, Drying, Solvent Recycling.

Pharmaceutical: The pharmaceutical industry has a need for an evaporation solution that covers a wide range of applications. The rotary evaporator is the best choice for gentle evaporation: Concentration, Drying, Re-crystallization, Synthesis.

 Looking to buy?

AI’s rotovap’s are UL- and CSA-certified and CE-compliant, allowing you to optimize your package with larger ancillaries and advanced vacuum controllers. We offer rotary evaporator models ranging from 2 liters to 50 liters so that you can choose accordingly based on your process requirements.

Check out our wide selection of Across International’s rotovaps and secure one for your lab today!

If you are looking to purchase a new rotovap evaporator for your lab, we have a wide range of scientific instruments available. Call us for more details and get the right Laboratory equipment for your Lab needs.