1. Mode of action of artificial pervaporation membranes

It is the thin film that controls the selective passage of substances. It is widely accepted that the selectivity and permeability of pervaporation membranes result from the effects of solubility and diffusion of molecules in the membrane material . The commonly accepted mechanism for material transfer involves three steps: first, selective absorption in a layer forming a kind of upstream membrane sheet, then selective diffusion through the membrane material, and finally vapor desorption on the downstream side of the membrane. Each of these three steps contributes to selectivity and permeability. In general, elastomers are preferable to glassy polymers, as liquids are more soluble in them. However, a high concentration...