Operating A High Vacuum Pump

Before initial operation of the vacuum system, make sure that you have received training from the head of the group or their representative and that you are equipped with appropriate personal protective equipment.

A cold trap serves as a condensation tool that safeguards vacuum lines or pumps from contamination. To maintain the integrity of a vacuum pump under lower pressures, it's recommended to employ a cold trap. This aids in condensing solvents and volatile liquids, preventing contact with these substances and safeguarding the vacuum pump from harm. It's advisable to incorporate a cold trap between rotary evaporators and the pump when utilizing one. When employing a cold trap:

Starting up

  1. Connect a clean and dry trap to the pump and to the vaccum line (grease it).
  2. With the dewar lowered and the system closed to air, turn the vaccum pump on and ensure vacuum preformance is leak free. Especially for working in an inert atmosphere in the presence of an Argon.
  3. Connect your flask to the vacuum line.
  4. Place the trap carefully into dewar half filled with liquid nitrogen and open the valve.

If liquid oxygen (blue color) is suspected to have been condensed, call 08-934-2999 immediately.

Shutting down

  1. Carefully remove the dewar with liquid nitrogen and turn off the pump (read below!).
  2. Always close the valve between the vacuum vessel and the pump before shutting off the pump.
  3. To avoid sucking vacuum oil into the system, release the vacuum immediately, after shutting down the pump. 
  4. Allow the trap to warm up to the room temperature before disposing of any solvents.
  5. If the cold trap is likely to have condensed toxic or corrosive vapors, the entire assembly must be placed in the fume hood overnight.
  6. Wash the trap.

Use personal protective equipment: safety glasses,  lab coat, closed shoes and gloves. For liquid nitrogen, use also: full face shield and gloves for cryogenic substances.

Always make sure the trap is removed from liquid nitrogen prior to turning off vacuum, as there is a potential for the formation if liquid oxygen (blue color), in nitrogen cooled vessels - it may cause serious explosion.