4. Membrane characteristics

Tables 3 , 4 and 5 show the characteristic values of commercially available membranes, according to their current use. They can be used to determine their permeability and selectivity. However, the type of variable differs from one process to another. Moreover, in most cases, the values depend on the conditions prevailing in the membrane-energy-medium intersection. As a result, extrapolation to other conditions is always hazardous. It is therefore preferable to carry out preliminary tests on a pilot plant, the results of which can be easily extrapolated, especially as membrane processes, by virtue of their modular design, are not very sensitive to scale effects, at least as far as permeability and selectivity are...