image of the Apiezon PFPE501 carton and tube

High Temperature Vacuum Distillations

How to use Vacuum Grease with high temperature vacuum distillations

Choosing your Vacuum Grease

Firstly, check you are using the right grease for the job. Our high temperature greases are Apiezon PFPE 501 and Apiezon H grease.

Benefits of Apiezon PFPE 501:

  • High temperature – up to 250°C
  • Ultra-high vacuum – vapour pressure at 25°C of 1.3 x 10-12 torr
  • Excellent lubricity – easy to separate glass joints after use
  • Very inert, compatible with almost all materials and solvents

To learn more about the use of PFPE 501 high vacuum grease in Short Path Distillation systems visit Short Path Distillation.

Benefits of Apiezon H grease:

  • High temperature – up to 240°C
  • High vacuum – vapour pressure at 20°C of 1.7 x 10-9 torr
  • Easy to apply
  • Easy to remove
  • Creep resistant

If you need help making the right choice for your application we’re always happy to help: Contact the Apiezon Technical Helpline

Applying your Vacuum Grease

After selecting the best grease for your application, ensure your glassware joints are clean. All residues of grease or distillate should be removed and the glassware rinsed with a suitable solvent. The solvent should then be dried fully before grease application.

A thin smear of grease should be applied to the top 1/3 of the male joint. This can be applied directly from the tube or by using a gloved fingertip to assist. Using too much grease or applying too close to the bottom of the joint can result in contamination.

Join the glassware with a twist as they seat, the grease should now cover a thin layer at the top of the joint. No cracks or gaps in the grease should be visible, further twisting will remove these if enough grease has been applied.

Grease should be fully removed and re-applied after every distillation to avoid stuck joints.


Removal of Apiezon PFPE 501

Wipe off excess grease with a lint free cloth. Residual grease can be cleaned using a perfluorinated solvent. For stringent cleanliness a further stage using acetone is recommended.


Removal of Apiezon H and other Apiezon Hydrocarbon Greases

Wipe off any excess grease with a soft clean lint free cloth. Any residues of grease can be washed away with warm soapy water or by using any aromatic hydrocarbon solvent (toluene, xylene). For a more environmentally friendly solvent, we recommend limonene. Apiezon H grease cannot be cleaned using alcohols (ethanol, IPA) or ketones (acetone, MEK).

If you need any advice about selecting the right grease for your application please contact us.