Operator`s manual

Chapter

Revision 004, 12/09 27

Cold Trap Condenser

Under conditions of high vacuum, vapor pressure of the solvent collecting on the

condenser is much lower than that of the product. When vapor molecules leave the

product in a vacuum concentrator, they migrate toward low-pressure areas in the

condenser. Upon contact with the condenser, the vapors release their heat energy

and condense. Whether or not ice forms is dependent on the chemical properties of

the solvent. Efficient evaporation rates are dependent on maintaining this vapor

pressure differential.

These migrating vapors can be pulled directly into the vacuum pump if condensation

does not occur. BenchTop series freeze dryers can be utilized as a Cold Trap

Condenser Module to condense and collect vapors being driven out of a product in a

vacuum concentrator. Condensing the vapors prevents them from migrating to the

vacuum pump and causing damage.

Product Requirements

Before using a Cold Trap Condenser, consider the following:

• Freezing and condensing points of solvents.

• Overall volume.

• Solvent properties, such as toxicity.

Note: This process is completely product dependent, so each application will vary in terms of

temperature requirements and process time.