KD Scientific Centrifan PE - Manual (Page 24)

Chapter 3
3-2 Centrifan TM PE Personal Evaporator
3.2 Set-Up the Cold Trap
(not included in Centrifan TM -PE- Lite version)
3.2.1 Low-Boiling Solvents
a) Fill cold trap with approximately 1L of the desired solvent into the top of the dry ice
trap until the level is about 15cm deep. In most cases, denatured ethanol is an
appropriate solvent.
Note: The solvent that should be used in the cold trap is dependent on the solvent
that is being removed from the solvent. If the temperature of the cold trap is too
low, it is possible that the evaporated solvent may freeze in the trap or tubing and
cause a blockage, thereby restricting the flow of recirculating gas in the system.
b) Gently drop several dry ice pellets into the trap to begin the chilling process of the
cold finger at the center of the trap. Add enough dry ice to maintain the cold
temperature of the trap for the period of time required for the drying operation.
Replace the cover of the trap to minimize the loss of the solvent through evaporation.
Typical drying rates of some common solvents are presented in Table 3-1.
Table 3-1: Drying Rates for Typical Solvents
Solvent Rotor* Total
Volume in
Rotor
Temp.
°C
Time to Dry
Rotor
Methanol
A 6 X 10mL 40 60 min
Water A 6 X 5mL 40 3 hrs
Hexane A 6 X 10mL 40 15 min
Acetone A 6 X 10mL 40 35 min
Isopropyl Alcohol A 6 X 10mL 40 70 min
DMSO A 6 X 1mL 40 12 hrs
Methylene Chloride
A 6 X 10mL 40 25 min
AcN/H20 (70/30) A 6 X 10mL 40 3 hrs
Methanol B 8 X 1mL 40 65 min
Hexane B 8 X 1mL 40 15 min
Acetone B 8 X 1mL 40 20 min
Isopropyl Alcohol B 8 X 1mL 40 50 min
DMF B 8 X 1mL 40 4 hrs
Ethyl Acetate B 8 X 1mL 40 25 min
Methylene Chloride B 8 X 1mL 40 18 min
Acetonitrile
B 8 X 1mL 40 35 min
AcN/H20 (70/30) B 8 X 1mL 40 3 hrs
*Rotor Key
A 6 x 20mL Scintillation Vial
B 8 x 1.6mL Microcentrifuge Tube
C 8 x 16mm x 100mm Test Tube