Operating A High Vacuum Pump
- Connect a clean and dry trap to the pump and to the vaccum line (grease it).
- With the dewar lowered and the system closed to air, turn the vaccum pump on and ensure vaccum preformance is leak free.
- Connect your flask to the vaccum line.
- 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.
- Carefully remove the dewar with liquid nitrogen and turn off the pump (read below!).
- Always close the valve between the vaccum vessel and the pump before shutting off the pump.
- To avoid sucking vaccum oil into the system, release the vaccum immediately, after shutting down the pump.
- Allow the trap to warm up tp the room temperature before disposing of any solvents.
- If the cold trap is likely to have condensed toxic or corrosive vapors, the entire assembly must be placed in the fume hood overnight.
- Wash the trap.
Use personal protective equipment: safety glasses, a 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 vaccum, as there is a potential for the formation if liquid oxigen (blue color), in nitrogen cooled vessels - it may cause serious explosion!!!