The rotary device (rotovap) is one of the laboratory equipments that are used to remove solvents effectively through the evaporation process. The rotary evaporation process is one of the most widely used methods of solvent evaporation due to the optimal performance of extraction and distillation.
In addition to the continuous distillation of volatile solvents, rotary devices are also used for concentration, crystallization, drying, separation, and solvent recycling, and are used in various fields and applications, including the pharmaceutical, chemical, and biotechnology industries.
Features of the rotary device
Special glass containers for fat-free use
Diagonal and vertical model
For flasks from 50 to 3000 ml
Speed range from 20 to 280 rpm
Easy height control by precision motor with up/down buttons
Nitrile PTFE and NBR double joint vacuum seal
Anti-wear, anti-aging, anti-chemical
The tilt angle is adjustable
The included water bath is made of stainless steel
Rotary device safety mechanism
Bath body two coats
Low water level detection and automatic stop function
Controller: internal digital controller with LCD display
How does a rotary machine work?
They work on the principle that solvents have a range of boiling points that decrease under reduced pressure. The evaporating flask rotates at a certain speed, forcing the material to form a large surface of a thin film on the inner wall of the flask. The flask is heated uniformly and the lower boiling point vaporizes rapidly. Recycling of the solvent stream after cooling is done by the glass condenser in the receiving flask.
Key benefits of using a rotary machine
Users can perform solvent removal faster and more efficiently than evaporation under atmospheric pressure, thus saving time and increasing productivity in the laboratory. In part, this rapid evaporation is due to the formation of a film on the inner surface of the flask, which greatly increases evaporation. So solvent removal is relatively fast (depending on volume and solvent). Rotary evaporators are simple to use and are commonly found in laboratories.
What factors are important in choosing a rotary machine?
One of the most important considerations for choosing a rotary evaporator is the type of solvent. Understanding the properties of the solvent is useful because it informs the user about the total vacuum required.
The boiling point of the solvent in vacuum is significantly reduced, for example:
Boiling point at 1000 bar
Boiling point at 53 mbar
81 degrees Celsius
7.7 degrees Celsius
78.4 degrees Celsius
19 degrees Celsius
It is necessary to monitor the low boiling points so that the bath temperature does not exceed these temperatures.
It is critical to consider heating and cooling capacity. The temperature difference between the solvent solution and the condenser must be sufficient. Typically, the condenser is cooled using dry ice or circulating tap water, but rotary chillers can be used and are useful because they are less labor intensive. Circulators are greener, save water and are more cost-effective over a period of time. They also prevent potential laboratory flooding.
Sewing automation and accessories can ensure workflow when using rotary evaporators. Some automatic features such as motorized lifters and automatic welding spot detection can minimize operating time.