Salt Rejection of Electrolyte Solutions

Salt rejection of a single electrolyte by a nanofiltration membrane in the absence of Donnan contribution can be described by Eqs. (12.9) and (12.10) according to the work of Spiegler and Kedem [57]. With ceramic nanofilters the Donnan contribution has to be taken into account due to the amphoteric 

12 — TRANSPORT AND FOULING PHENOMENA IN LIQUID PHASE SEPARATION 

The evidence of electrokinetic salt rejection by a microporous inorganic material was given by Jacazio et al. [63] based on the model of Osterle [26-28]. Experiments were carried out on the salt rejecting properties of compacted clay through which saline solutions were forced under high pressures. In accordance with the model the performance of the porous material was shown to depend on three main parameters the ratio of the Debye length to effective pore 

Another work from Rios et al. [65] also deals with performance of a positively charged y-alumina membrane fed with single NaCl, MgCl2, Na2S04 and MgS04 solutions at various concentrations (10 to 10 mole-H), or even with electro- 

Rejection with a 7-alumina membrane of mixed electrolyte water solutions [64] 

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