Lyophilization, drying with minimal residues, and molecular distillation

These applications are beyond the vacuum range of diaphragm pumps. They call for vacuum systems with ultimate vacuums of 10-1 to 10-3 mbar; single- and two-stage rotary vane pumps provide these pressures at various volume flow rates. A convenient option especially for chemical applications is our chemistry-HYBRID pump RC 6, a combination of a rotary vane and a chemistry diaphragm pump. The special design often allows operation without an additional cold trap. The integrated diaphragm pump enhances condensate compatibility, reduces service needs and results in a longer pump life. The lower service demands greatly reduce lifetime costs of the RC 6 pump compared with a conventional rotary vane pump.

Process requirements

  • low ultimate vacuum, depending upon the process conditions
  • volume flow rate appropriate to system size (laboratory, pilot or production plant)
  • regulation of shelf temperature and vacuum level, depending upon material to be dried (in freeze drying processes)

Pump requirements

  • ultimate vacuum to 10-3 mbar
  • depending upon process conditions, excellent pump condensate compatibility may be important for extended service life of the pump
  • low ultimate vacuum even with open gas ballast for continuous condensate purge
  • chemical resistance is an important consideration when drying substances containing solvents
  • chemistry-HYBRID pump RC 6 is recommended