ABSTRACT
Among the large variety of membrane operations, membrane contactors (MCs) represent relatively new membrane-based devices that are gaining wide consideration. All traditional stripping, scrubbing, absorption, and liquid–liquid extraction operations, as well as condensation, dehydration, crystallization, and phase transfer catalysis, can be carried out according to this configuration. With respect to conventional membrane systems, MCs have some important advantages such as high interfacial area per volume unit, low operating temperatures and pressure, high rejection, modular design, easy scale-up, less membrane fouling, and low sensitivity to concentration polarization phenomenon. Drawbacks are related to the presence of an additional mass transport resistance (the membrane itself) and to the rather limited range of the operating pressures below the breakthrough threshold. Therefore, the performance of MCs strongly depends on the properties of the membranes used.
The chapter will address the working principles, the fundamental concepts, and the transport phenomena through microporous hydrophobic membranes of interest in membrane distillation, membrane crystallization, and membrane condenser operations.
