Rotary Evaporators for laboratory - uses
Our rotary evaporators by the well-known laboratory equipment manufacturers Heidolph and IKA are mainly used laboratories in chemistry, research, science and industry as well as occasionally in various kitchen in the field of gastronomy and food technology, wherein in the molecular kitchen rotary evaporators are used for cooking and preparing dishes. However, as a fundamental piece of laboratory equipment a rotary evaporator is mainly intended for distillation in the laboratory, primarily for the evaporation of solvents. Distillation with rotary evaporators is largely a standardised process in every chemical laboratory and nowadays fully-automated rotary evaporators are also being utilised. At a given temperature and pressure they evaporate the substances to be distilled whereby solvents and the substance they contain are separated.
Lab Rotary Evaporators - structure
A rotary evaporator for use in the laboratory usually comprises a water or oil-filled heating bath or water bath, a vapour tube at the end of which there is an evaporator flask, a cooler with a vacuum attachment and a collection flask. At the upper end the rotatable vapour tube passes through a shaft seal into the recirculating cooler and is rotated by means of a continuously adjustable motor. The heat required for distilling the solvents is provided via the heating bath/water bath, or an oil bath for achieving higher temperatures, into which the evaporator flask is immersed. Frequently an external pump, usually a vacuum pump, is connected in order to reduce the pressure. For vacuum distillation most laboratories use a modular system consisting of a rotary evaporator, vacuum pump and recirculating cooler.
Principle of Rotary Evaporators - function
In principle a rotary evaporator for the laboratory is an apparatus for vacuum distillation with an evaporator flask rotating about its longitudinal axis. In comparison with conventional distillation where the content has an approximately uniform temperature, through its function a rotary evaporator has two advantages: it increases the surface area and accordingly the rate of evaporation. Through the rotation of the flask bubble formation and welling up of the solution are prevented as evaporation mainly takes place from the very thin fluid film on the flask wall. The functional principle of the rotary evaporator can be easily explained through its structure. Due to the warming of the evaporator flask in the heating bath the solvent/substance to be distilled evaporates. The vapour flows via the vapour tube into the cooler where it condenses on the cooling surface and flows into the collection container. Clean separation of the substances is achieved if their boiling points differ and are not too close to each other, such as in mixtures of methanol and ethanol. Through a rotary evaporator with a vacuum pump the boiling temperature can be reduced whereby solvents with a higher boiling point can be evaporated at lower temperatures than would be the case under normal pressure. In the case of lower boiling temperatures the breakdown of temperature-sensitive substances which are to be released from the solvent is prevented. The shaft seal seals the rotating vapour tube off from atmospheric pressure and ensures a constant vacuum in the interior of the apparatus.
Rotary Evaporator - accessories
Our top-class rotary evaporators by renowned manufacturers are characterised by their safety, ease of use and high service-life during many years of continuous operation as well as the functional feature of being able to change individual parts or add accessories. Depending on the evaporator model and manufacturer you can order various replacement parts and accessories for rotary evaporators such as various coolers, flasks, vacuum pumps, regulators, software, protective hoods, clamps, heating bath liquids and many other components for the rotary evaporators we offer.