## Rotary evaporator Rotavap is the abbreviation for rotary evaporator. It consists several parts including rotation motor, water cooling, water bath, liquid container and a vacuum pump. The following figure shows the rotavap in the lab. ![[Drawing 2023-11-09 17.40.03.excalidraw.svg]] - The motor controls the rotation of the flask or connected centrifuge tube. The speed may be adjusted using the knob for rotation control. - The vacuum is provide by a [Rotary vane pump](https://en.wikipedia.org/wiki/Rotary_vane_pump), which is a typical device for [[Vacuum system|vacuum system]]. The vacuum level can be controlled in the pump panel. - Flask can be connected to the ground glass joint, and a clamp could be used for fixing. However, if using the centrifuge tube, the the clamp may not work and the ground glass joint cannot ensure good airtight. Therefore, hold the tube until the vacuum is established. - Water bath temperature may be adjusted in the thermostat control panel. Plastic balls covers the water surface, in order to eliminate the evaporation of water. If the water level is too low, add more water if no good contact is made. - Use the handle to adjust the height of the flask/tube. - Stopcock controls whether the parts connected to flask are under vacuum or not. Use vacuum grease to ensure good airtight and lubrication. When drying finish, rotate the stopcock slowly to make sure the outer air do not gets into the system too fast and make damages. - Cooling water is connected to the external water source, to condense the evaporated solvent into the receiving flask. >[!Info] >See more on [rotary evaporator wiki page](https://en.wikipedia.org/wiki/Rotary_evaporator) and the file by ucalgary https://www.chem.ucalgary.ca/courses/351/laboratory/rotavap.pdf.