In contrast to simple gravimetric filtration, utilizing a vacuum pump creates a pressure differential to more effectively draw the fluid through the filter.

Care should be taken to match the pump to the application, as an insufficient vacuum will prolong the process while an excessive vacuum can collapse or tear the filter paper. One simple solution for managing the vacuum level is to equip the pump with a vacuum regulator and gauge.  


Pump selection is influenced by various factors including filter size, number of filters (if using a manifold), vessel size, and media type. Aqueous solutions do not require the same level of chemical compatibility as strong solvents and acids. Larger vessels require higher flow rates, while viscous media require a deeper end vacuum.



Considerations for selecting the optimal pump include:


  • Flow rate in proportion to the system volume  
  • Oil-free operation with excellent chemical compatibility
  • Adjustable control of vacuum levels
  • Solvent recovery options at both the inlet and the outlet



Contact us to discuss KNF pumps and your unique application with one of our technical experts.  


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