Cadmium(II) transfer using (TiOAC) ionic liquid as carrier in a smart liquid membrane technology

The transfer of cadmium(II) from acidic chloride solutions through a smart liquid membrane technology was investigated in a microporous polypropylene hollow fiber membrane contactor. The organic solution of tri-isooactylammonium chloride (TiOAC) in Exxsol D100 was used as carrier. The acidic chloride feed solution containing the metal was passed through the tube side, and the pseudo-emulsion of the organic solution and NH4OH was passed through the shell side in counter-current mode, using a unique contactor in the process. In the pseudo-emulsion based hollow fiber membrane with strip dispersion (PEHFMSD) technology, the aqueous strip solutions of ammonium hydroxide are dispersed in the organic solutions in a tank with a mixing arrangement to provide a strip dispersion. This strip dispersion circulates from the tank to the membrane module to provide constant supply of the organic solution to the membrane pores. Different hydrodynamic and chemical variables, such as variation in feed acidity, metal concentration in the feed, carrier concentration in the organic phase, variation in feed, strip and organic phase volume ratios and variation in the feed and pseudo-emulsion flows, were investigated. Mass transfer coefficients were calculated from experimental data.