By following these simple guidelines, costs can be reduced and results can be optimized.
Choosing Vacuum Pressure
Vacuum Controllers play a critical role in regulating evaporation experiments: without one, experiments can only run at maximum vacuum pressure. Vacuum Controllers reduce the risks of sample loss and lab contamination, and they may be programmed to reduce bumping and foaming and perform automatic distillations.
Once a Vacuum Controller has become part of your lab set-up, how is the appropriate vacuum for the solvent calculated?
The vapor pressure temperature under vacuum of most common solvents can be calculated by using the following formula introduced by Reckhard1 in 1958. Refer to Table A for a listing of physical constants for common solvents.
|Log P = 3.006||[Ts Tp]