Thin coatings water purification

Separation of gas and liquid mixtures using polymer membranes has now become accepted as a unit operation in many chemical process flows. Most barrier coatings are applied as dense films, but for applications such as gas separation a very thin layer is needed so that gas diffusion can take place in a sufficiently short time period. Water purification membranes are usually a thin, dense polyamide film on a porous support forming a composite membrane. Fuel cell membranes in contrast involve dense films of proton exchange materials. In many cases, control of phase separation and understanding the underlying thermodynamic processes are key elements in successful membrane constmaion. 

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