Process Description - Wiped Film Distillation or Evaporation

short path wiped film process illustration

Also known as Molecular Short Path Distillation, Thin Film Distillation, and Short Path Evaporation.

Feed liquid is admitted into still under high vacuum, immediately spread into a very thin film and forced quickly down the evaporation surface. Heated walls (orange) and high vacuum (yellow) drive the more volatile components (distillate) to the closely positioned internal condenser as the less volatile components (residue) continue down the cylinder. The resulting fractions, thus separated, exit through individual discharge outlets.

Depending on the application, the desired product is either the distillate or the residue fraction. Small amounts of condensable low MW compounds collect in cold trap upstream of vacuum system. For high solvent loads, an optional external condenser may be installed immediately downstream of the still. (With external condenser incorporated, the internal condenser should be removed to provide a typical “WFE” or Wiped-Film Evaporator or Short Path Evaporator configuration.)

Pope adds superior design and construction to the basic wiped-film/short path still process. This has enabled Pope stills to sustain pressures down to one micron for molecular distillation.

Typical Applications

  • Biomaterial Concentration
  • Molecular Distillations of Esters, Fatty Acids, Mono, Di, Omega 3 & Triglycerides
  • Vitamin, Nutraceutical, Essential Oil Isolation
  • Oil Deodorization
  • Water Removal – ppm Level
  • Solvent Recovery
  • Vacuum Distillation of Terpenes, Terpenoids
  • Chlorophyll, Phytosterols, Fat & Wax Removal, with clear distillate
  • Purification After Extraction, (supercritical CO2, butane, hydrocarbon, ethanol, etc.)
  • Concentration of Botanicals & Essential Oils
  • Fractional Distilling via Hybrid Technology
  • Improved Evaporation over Rotary Evaporators, Kugelrohr & Rotovap Apparatus