Pervaporation (also known as pervaporative separation) is an exciting continuous membrane separation process for mixtures of liquids. Separation occurs by volatilization across a non-porous membrane and is usually run under vacuum with condensation of the permeate. The term pervaporation is derived from the two steps of the process; permeation through the membrane by the permeate and the subsequent evaporation into the vapor phase.
Pervaporation systems can be employed to strip organics from water, for recovery of high value-add compounds such as flavors, aromatic compounds, pharmaceutical components, recovery of thermally sensitive materials, breaking azeotropes, and dehydration of organic solvent systems.
The advantages of pervaporation over conventional separation technology include energy efficiency, no regeneration steps, no additional solvents or carrier systems, and minimal waste, making it a powerful emerging separations process.
Typically at least one of the liquids is organic, differentiating pervaporation from membrane distillation.
Pervaporation processes are controlled by differing rates of diffusion of the components of the liquid mixture and the separation process is driven by partial pressure (temperature and concentration differences).
At the heart of a pervaporation module is a suitable non-porous membrane usually supported on a porous substrate, allowing the non-porous membrane to be as thin as possible. Both materials benefit from high service temperature, chemical inertness, and a high degree of chemical stability in the presence of aggressive chemical systems or extreme pH.
Eclipse Hollow Fiber Membranes® coated with our proprietary fluoropolymer-based dense membrane and coupled with our patented all-fluoropolymer potting system represent one of the most promising pervaporation systems on the market. While still early in its development, we are excited by the technology and are actively seeking partners in its development.