Limitations and Technical Challenges

While vapour permeation and hydrophilic pervaporation have readily found well-established areas for industrial application, in the case of organophilic pervaporation a clear industrial breakthrough has not yet been achieved. The reasons for this situation derive from the intrinsic character of this process and from the way some problems have been approached so far  

Although less discussed in the technical and scientific literature, permeate-side concentration polarisation may also become a problem when using thin selective films that require macroporous supports for mechanical stability [13]. 

These porous structures may hinder the transport of solutes away from the membrane downstream surface, causing a local increase of the solute partial pressure and hence a decrease of the driving force (19.1). Eventually, solute condensation may occur if the solutes local partial pressure surmounts its saturation vapour pressure. This problem becomes particularly relevant when dealing with high-boiling aroma compounds [14] and when pressure drop in the downstream circuit increases owing to poor module design. 

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