ABSTRACT
The solution-diffusion model is currently being used by the majority of the membrane community. An excellent summary of the applicability of this model for various membrane transport phenomena is given in the classic book by Crank and Park. It is possible to predict reverse osmosis performance data under different operating conditions. The method can be extended to the prediction for the separation of different solutes, either organic or inorganic, if the separation data of sodium chloride solute are known for a membrane. Apparently, Sourirajan and co-workers assumed the presence of pores in any reverse osmosis membranes for which they applied their transport equations, whereas, for Lonsdale, pores were considered as defects that prevented membranes from achieving the highest solute rejection that is the intrinsic property of the polymeric material.
