Pervaporation & Vapor Permeation Membrane Processes for the Selective Separation of Liquid and Vapor Mixtures

Pervaporation and vapor permeation are membrane-based processes which have been proposed as alternatives to conventional separation technologies.  Applications range from organic solvent removal from water, ethanol or butanol recovery from dilute fermentation broths, solvent/biofuel dehydration to meet dryness specification, and organic-organic separations such as the removal of sulfur compounds from gasoline. Unlike membrane filtration processes which rely on an applied liquid pressure gradient and size sieving to accomplish a separation, pervaporation and vapor permeation separate compounds based on a chemical activity driving force and the sorption & diffusion of the compounds through the membrane.  These properties enable the separation of even miscible liquid mixtures such as ethanol-water solutions.

In this presentation, we will discuss the following:

• Process fundamentals
  • Solution-diffusion mechanism
  • Mass transfer
  • Energy issues
• State-of-the-science and future trends
  • Membranes (hydrophobic and/or hydrophilic,)
  • Modules
  • Processes
    • Pervaporation-Dephlegmation
    • Hybrid Processes
• Integration of Pervaporation with Fermentation Systems
• Development/Commercialization status