Hydrophobic materials are poorly wetted. They attract organics that are also non-polar. Processes such as desalination perform best with hydrophillic membranes because materials that would foul are not attracted to the membrane.
An example of good use of a hydrophobic membrane is removing microorganisms to sterilize air. The air tends to have fine droplets of water. A hydrophillic membrane would collect water in its pores to reduce flux and to provide some opportunity for organims to move through. A hydrophobic membrane sheds water as drops that form pools to be removed.
Last update 10-FEB-95