Dispersed liquid membrane systems are double emulsion drops. Two immiscible phases are separated by a third phase which is immiscible with the other two phases. The liquid membrane systems were classified into three types: (1) carrier mediated mass transfer, (2) mass transfer with reaction in the receiving phase, (3) mass transfer without any reaction involved. Copper extraction, phenol removal and solvent extraction were used as typical examples for each type of the membrane systems in the derivation of their mathematical models. Models with or without the consideration of film resistances were developed and compared. The models developed in this study can predict the extraction rate through dispersed liquid membranes theoretically. All parameters required in,the models can be determined before an experimental extraction run.

Experimental data from this study (.copper extraction) and from literature (phenol removal and solvent extraction) were used to test the models. The agreements between the theoretical predictions and the experiemental data were very good. The advantages, of dispersed liquid membrane systems over traditional methods were discussed. The models developed in this research can be used directly for the design of dispersed liquid membrane systems. The results of this study represent a very significant step toward the practical applications of the dispersed liquid membrane technology.