The rotary evaporator is a device that uses a rotary evaporation flask to increase the evaporation area and place it in a water bath under reduced pressure while rotating and heating, so that the solution in the flask is diffused and evaporated. It is a basic instrument for concentration, drying and recycling in chemical industry, institutions of higher learning and scientific research laboratories for manufacturing and analysis experiments. Reliable and reproducible distillation results typically found on other, more expensive distillation equipment can be achieved.