Showing 1–12 of 26 results

Rotary evaporators are currently for sale with the favorable price and sincere service.

A rotary evaporator (rotovap or rotatvap) refers to a kind of equipment for solvent evaporation under reduced pressure, which is composed of a vacuum system, a heated water or oil bath, a condenser and a motor that rotates the evaporation flask. As its name suggests, what is special is that the evaporation flask can rotate.

introduction to Rotary evaporator

Rotary Evaporator --- Parts and Functions

A complete rotary evaporator is generally composed of the following parts, which cooperate with each other and all play an essential role in the working process of a rotary evaporator.

1. Evaporation Flask

The sample can be evaporated at the evaporation flask.

2. Rotary Motor

The rotary motor is used to drive the evaporation flask rotating at a continuous and constant speed in order to obtain a larger evaporation area and higher evaporation efficiency.

3. Vacuum System

The vacuum system can be used to reduce the pressure within the rotary evaporation system so that the solvent will have a lower boiling point at a reduced pressure.

4. Heating Bath

The heating bath is usually a hot water bath, which can be used to heat sample in the evaporation flask and regulate temperature.


Rotary Evaporator

5. Condensate Pipe

There are double spiral serpentine condenser coils, vertical condensing glass assembly and other types of condensate pipes, which are used to condense the evaporated sample.

6. Evaporation Pipe

The evaporation pipe has two functions. One is to protect the sample during its rotation, and the other is to enable the vacuum system to suck out samples.

7. Receiving Flask

The receiving flask can recycle the sample after it’s being condensed.

How does a Rotary Evaporator Work?

A rotavap evaporates solvents from samples by utilizing the principle that the solvent will have a lower boiling point at a reduced pressure. Specifically speaking, the stepless speed regulation is adopted to make the evaporation flask rotate at a constant speed. By the rotation, materials can form a large area of uniform thin film on the inner wall of the flask. The evaporation flask is heated evenly by a water or oil bath, and materials, with a lower boiling point, is evaporated rapidly under the vacuum condition. The solvent steam is recycled in the receiving flask after being cooled by the high efficiency glass condenser.

How to Install a Rotary Evaporator?

1. Insert the pole supporting the glass condenser, and then tighten the two stainless steel screws to fix it.

2. Sleeve the evaporation tube into the shaft of the reduction gear box and tighten the pressure cap. Install parallel rings, O-rings, and T-rings.

3. Install the glass four-way. After the four-way interface and the T-ring are in proper positions, tighten the large spiral ring, but be careful not to tighten it too tightly, otherwise the service life of the O-ring will be shortened.

4. Install the condensate bottle. Coat the interface of the condensate bottle with vacuum grease evenly, insert it into the ground opening of the four-way, and then tighten the fixing screws on the belt holding block. The connecting position and angle of the glass four-way and the sealing ring can be changed by adjusting the position of the screw and the long hole of the holding belt, and the best vacuum state can be achieved.

5. Install the receiving flask and evaporating flask on the rotary evaporator. After applying vacuum grease evenly on the grinding mouth, clamp it with a clamp.

6. Add appropriate amount of water to the water bath, turn on the power, set the heating temperature, and the heating indicator light is on, and it can be used normally.

7. With the lifting height and moving distance position of the rotator of the rotary evaporator, place the evaporating flask in a proper water bath.

8. Description of the lock sign: Twist the handle to the left, loosen the locking device and adjust it to a suitable height, and then tighten it to the right.

How to Use a Rotary Evaporator?

1. Use a hose to connect to the condensate tap, and use a vacuum hose to connect to a vacuum pump to vacuum.
2. Pour water into the heating tank first (pure water is best). If you use tap water, please leave it for a day or two before using it.
3. The method of adjusting the angle of the main unit: Just loosen the main unit and the column connecting screw, the main unit can be tilted between 0-45 degrees.
4. Turn on the condensate, turn on the power supply, connect the evaporating flask to the host (don't let go), turn on the vacuum pump to reach a certain degree of vacuum, and then release it.
5. The method of adjusting the height of the main engine: Press down the pressure bar located at the bottom of the heating tank, adjust the radian to make the main engine reach the proper position, and then leave the pressure bar to reach the required height.
6. Turn on the speed control switch and the green light is on, adjust the speed knob on the left side, and the evaporating flask starts to rotate. Turn on the temperature control switch and the green light is on, adjust the temperature control knob on the left side of the heating tank to start automatic temperature control heating, and the rotary evaporator enters the trial operation. Once the temperature and vacuum reach the required range, the solvent can be evaporated to the receiving flask.
7. Stop the low-temperature coolant circulation pump, stop the water bath heating, turn off the pump circulating water, pour out the solvent in the receiving bottle, wash the buffer ball, and stop the rotation of the receiving bottle after steaming, then vent the atmosphere, then stop the water pump, and finally remove it Distillation flask.
8. After the evaporation is completed, first turn off the speed control switch and the temperature control switch, and press the lower lever to make the host rise. Then turn off the vacuum pump and open the vent valve above the condenser to communicate with the atmosphere. Remove the evaporating flask to complete the evaporation process.

Tips on Using a Rotary Evaporator

Keep the whole equipment sealed, so that the vacuum can be maintained. In this way, the continuous feed system can continue during the whole process. What’s more, the vacuum can keep extracted solvents pure. So users need to keep the flask clamp tight to prevent air from coming into the equipment.
In addition to mastering the use of rotovap, users should also master the matters needing attention in rotovap:The most important thing is to handle the glass pieces gently, wash and dry them after use; Secondly, the heating tank should be filled first and then electrified. Dry burning without water is strictly prohibited. A small amount of vacuum grease should be uniformly applied to the grinding instrument before installation. To ensure the safety of the precious solution, the simulation test should be done first. At the end of the work, close the switch and unplug the power plug.

What are Applications of a Rotary Evaporator?

A rotary evaporator is mainly used for the process of evaporation, concentration, crystallization, drying, separation, and solvent recovery, and especially used for the continuous distillation of large amounts of volatile solvents under reduced pressure. With so many application purposes, there is no doubt that a rotary evaporator can be applied in many areas. For example, it can be used in the small and pilot experiments and production in the biological, pharmaceutical, chemical fields and even food-making industries.

What are Advantages of a Rotary Evaporator?

1. Higher evaporation efficiency.

There are several factors contributing to higher evaporation efficiency. Firstly, the rotating flask can rotate at a constant speed, and materials can form a widespread film on the inner surface of the flask, which improves the evaporation efficiency greatly. Secondly, the high-efficiency glass condenser can improve the evaporation efficiency as well. Last but not least, continuous feeding and high vacuum degree are another factors.

2. Better security.

The stainless steel and aluminum alloy are widely used in the mechanical structure, and all glass parts are made of heat-resistant high borosilicate glass, which ensure a better security. Besides, the water/oil bath can be equipped with transparent covers to prevent splashing, and anti-explosion frequency changer and dynamo are available as well. All of these designs contribute to better security.

3. More convenient operation.

It’s much more convenient to use a rotary evaporator, because of the electrodeless speed regulation, digital display K Type Sensor and intelligent temperature control and other designs adopted by it.

How to Maintain a Rotary Evaporator?

1.Check the instrument carefully before use to see if the glass bottle is damaged and whether the interfaces are consistent. Be careful to handle it gently.
2. Wipe each interface with a soft cloth (can be replaced by a napkin), and then apply a little vacuum grease. Be sure to cover the vacuum grease after use to prevent dust from entering.
3. Each interface should not be tightened too tightly, and should be loosened regularly to avoid long-term locking and causing the connector to seize.
4. Turn on the power switch first, then let the machine run from slow to fast, When the machine is stopped, the machine should be in a stopped state, and then turn off the switch.
5. The Teflon switches of the rotary evaporator should not be tightened excessively, which may damage the glass.
6. After each use, you must use a soft cloth to wipe off all kinds of oil stains, stains, and solvent remaining on the surface of the machine to keep it clean.
7. Loosen the PTFE switches after the machine stops, and the PTFE piston will be deformed if it is in the working state for a long time.
8. Clean the sealing ring regularly by removing the sealing ring, checking whether there is dirt on the shaft, wiping it with a soft cloth, then applying a little vacuum grease and reinstalling it to keep the shaft and the sealing ring smooth.
9. Water must not enter the electrical part of the rotary evaporator, and it is strictly forbidden to get wet.

Related Products

Request a Quote

Get in Touch with Us


Zhengzhou City, Henan Province, China






    related posts