We want to purchase a rotary evaporater for our lab for evaporating the solvents from plant extracts so can you please suggest me which one is best and easy to handle.
Rotary evaporators can cause foaming - they tumble the sample. This may be OK for your extract, howvever this may be a problem for some larger molecules as they can denature. In addition, there are many saponines in plants, these can foam beautifully ... not good for an active substance. The best rotary evaporator I know of is from Heidolph, however I encourage you to consider all the factors as all rotary evaporators have the aforementioned limits.
In our laboratory, we are using "Vacuum Rotary Evaporator for Vacuum Distillation and Essential Oil Extraction ". I hope this kind may help you much for extraction of plants.