Generally, a rotary evaporator is primarily composed of four components, including a water bath for heating, a motor for rotating the evaporation flask, a condenser for condensing the evaporated sample as well as a cold trap. Many people may wonder the role that a cold trap plays in a rotary evaporator. Well, it will be further discussed in the following parts.
What is a Cold Trap Used for?
A cold trap refers to a kind of device that prevents vapor or liquid from entering the measuring instrument from the system or from the measuring instrument into the system. Generally, the cold trap is used to prevent oil vapor from returning to the application equipment in the vacuum environment, which can cause application space being polluted. A U-shaped tube is placed in the refrigerant. When the gas passes through the U-shaped tube, the substance with a high melting point becomes a liquid, and the substance with a low melting point passes through the U-shaped tube for separation.
The Role that a Cold Trap Plays in a Rotary Evaporator
A cold trap usually plays an essential role in a rotary evaporator. As a trap, it can trap gas on a cooled surface in a coagulated manner. It is a device placed between a vacuum vessel and a pump for adsorbing gas or trapping oil vapor. In rotary evaporator equipment, cold trap plays a very important role. It is cylindrical and has two flanges on the upper and lower sides. The lead gasket is lined with a lead gasket and is connected to the vacuum pump and the suction container.
The cold trap has a good thermal connection to the condensing sheet arranged in a certain way through the copper ring, absorbing heat from the condensing sheet and keeping it at a low temperature of -30 °C. When the extracted gas passes through the condensing sheet, the water vapor and other gases in the gas solidify on the condensing sheet, increasing the degree of vacuum. The cold trap can work continuously, and it can be connected with power supply and water supply.