AP201 vapour booster pump fluid

Apiezon® AP201 is a hydrocarbon fluid prepared by molecular distillation and protected against oxidation by a thermally stable additive of matched vapour pressure. It has an auto ignition temperature of 305°C.

Features and Benefits

  • AP201 exhibits a fair degree of resistance to chemical degradation (so that high throughputs of air and water vapour can be pumped without damage to the fluid) and it can withstand limited accidental admission of atmospheric air at operating temperature.
  • The fluid has low viscosity, which permits easy filling and draining.
  • It does not attack synthetic rubbers used for seals and gaskets in vacuum systems.
  • It is non-irritant, non-toxic and environmentally non-polluting.


  • Furnaces
  • Vapour Booster
Technical data  
Typical ultimate vacuum achievable at 20°C (mbar) 6.5 x 10-5
Vapour pressure mbar:  
  20°C 5 x 10-6
  100°C 2.4 x 10-2
  150°C 6.5 x 10-1
Boiling temperature at 1.3 mbar (°C) (approx) 160
Molecular weight (average) 310
Viscosity cSt:  
  at 20°C 34
  at 100°C 5.0
  at 150°C 2.7
Pour point °C (approx) -30
Flash point °C 196
Fire point (°C) (approx) 204
Auto ignition point °C (approx) 305
Specific heat (cal/g/°C) 0.46
Latent heat (cal/g/°C) 69
Specific gravity at 25°C 0.862
Coefficient of expansion per deg C 0.0007
  (10 - 30 °C)
Refractive index at room temperature 1.476