Wetting criteria for the applicability of membrane distillation

A.C.M. Franken, J.A.M. Nolten, M.H.V. Mulder, D. Bargeman, C.A. Smolders

Research output: Contribution to journalArticleAcademic

293 Citations (Scopus)
344 Downloads (Pure)


Membrane distillation can only be applied on liquid mixtures which do not wet a microporous hydrophobic membrane. Solutions of inorganic material in water have such high values of surface tension (γLgreater-or-equal, slanted72x10−3 N/m) that the non-wetting condition is fulfilled for a number of hydrophobic membranes. As soon as organic solutes are present in the solution, the surface tensionγL will be lowered, and if the concentration of organic material becomes too high, wetting of the membrane will occur. By means of theoretical considerations a critical solute concentration or surface tension at which a homogeneous smooth material will be wetted (gq < 90/deg) can be calculated. For a (micro)porous membranes no such theoretical relation can be derived. Therefore, a simple experimental method is described to measure the maximum allowable concentration for a (micro)porous membrane. On the basis of these measurements, the maximum allowable concentration under process conditions can be determined.
Original languageUndefined
Pages (from-to)315-328
JournalJournal of membrane science
Issue number3
Publication statusPublished - 1987


  • IR-67258

Cite this