Koehler K87170, Operation And Instruction Manual

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19.
If a sudden increase in pressure is observed, coupled with the formation of
white vapors and a drop in the vapor temperature, the material being distilled
is showing significant cracking. Discontinue the distillation immediately and
record the fact. If necessary, re-run the distillation with a fresh sample at a
lower operating pressure.
20. Once the end point has been detected the distillation will stop automatically.
21. When the distillation has ended the Run Mode will switch to Cooling Down .
22. Lower the flask heater 50 to 10 cm. A fan will automatically blow air on the
pot flask to help cool it quickly.
23.
When the pot cools below 100 ºC the vacuum pump will automatically turn
off and the system will automatically vent to atmospheric pressure. The
Run
Mode will switch to Shutting Down.
24. Bring the temperature of the cold trap mounted before the vacuum pump back
to ambient temperature. Recover, measure, and record the volume of the light
products collected in the trap.
25. Remove the receiver and replace with another. Remove the flask and replace
with another flask filled with approximately 100 mL of a cleaning solvent
such as toluene or cyclohexane. Run a distillation cleaning cycle to clean the
unit. At the end of this cleaning run, remove the flask and receiver and blow a
gentle stream of air or nitrogen to dry the column.
WARNING!
Do not let sample or solvent drip onto the heating mantle. Care must be take to prevent
drips onto the heating mantle when the boiling flask is removed. Contaminamtion on the
heating mantle will damage it and can cause it to fail.
WARNING!
Do not use acetone or other non-petroleum products to clean the system. This will result
in damage to critical O-Rings in the system. This may result in serious injury to the user.
Use only petroleum solvents such as toluene or cyclohexane to clean the distillation
system.
Performing a Distillation 5-8