Ion exchange, electrochemical

An alternative ion exchange system has been developed by AEA Harwell in which an electrochemical potential is applied to the ion exchanger. The process referred to as electrochemical ion exchange, EIX, is a method of 

The suggested applications are in the removal of toxic, metal ions, precious metals, nitrates and corrosive anions and in the de-ionisation of water. The technique has been demonstrated in the removal of chloride and sulphate in the presence of borate/boric acid and for the removal of Co from feeds, which contain concentrations of 100 ppb, to undetectable levels. 

The general concept of the integration of ion exchange, which effectively increases the concentration of the metal ions to be recovered, with the metal deposition process to enhance the efficiency of the metal deposition can be applied with other separation/concentration methods. One of these methods is based on the use of crossflow membrane ultrafiltration [38]. The complexation-ultrafiltration of the dissolved metal ions allows the concentration of the solution prior to electrolysis. 

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Formation of single-phase ZnTe on zinc substrates at 640 K by using electrochemical ion exchange and chemical reaction/alloying with Te" species, supplied to the substrate as a vapor from TeCU-containing eutectic LiCl-KCl molten salts, was reported recently [118]. ZnTe films with a smooth dense surface and particle diameters less than about 0.8 p,m were obtained, by properly adjusting the TeCU content and the reaction time. 

Kuroda K, Kobayashi T, Sakamoto T, Ichino R, Okido M (2005) Formation of ZnTe compounds by using the electrochemical ion exchange reaction in molten chloride. Thin Sohd Films 478 223-227... 

T0702 Selective Environmental Technologies, Inc. (Selentec), Electrochemical Ion Exchange... 

Fig. 27. Cross-sectional view of the electrochemical ion exchange (EIX) electrode. (Adapted from [143]).

Critical for the control of system performance is the careful management of the pH and other electrolyte conditions within the electrode casings. Contaminants are recovered from the circulating electrolytes by both precipitation and filtration, by electrochemical ion exchange (EIX ), or by other ion-coUecting systems. 

Reduction Chorinated organics Co(II). Electrochemical ion-exchange. Electrosorption. 

Applications that we have touched upon include supercapacitors, battery materials, sensors, biosensors, catalysts, fuel cell electrodes, electrochemical ion exchange switches and others. Composite catalysts for fuel cells is an area that is rapidly expanding. Use of nanomaterials in all these applications is also an ongoing pursuit. Potential uses in ceramics and optoelectronics are also areas of interest. 

Henry, P., Van Lietde, A. (1998). Selective separation of vanadium from molybdenum by electrochemical ion exchange. Hydrometallurgy, 48(1), 73—81. http //dx.doi.org/10.1016/ S0304-386X(97)00060-1. 

The same electrochemical ion exchange process makes the polymer change its volume, so that polymer films shrink and swell following oxidation and reduction. This property suggested their use as actuators. In fact if poly(3-octylthiophene) [344] and PP [345] are electrodeposited onto a gold-coated polyethylene strip, redox switching induces bending of the strip. 

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