Electrodeposition, separations based

The electrochemical atomic layer epitaxy (ECALE) technique, also known as electrochemical atomic layer deposition (EC-ALD), is based on layer-by-layer electrodeposition. Each constituent of the thin him are deposited separately using underpotential deposition (UPD) of that element. UPD is a process wherein an atomic layer of one element is deposited on the surface of a different element at a potential under that needed to deposit the element on itself. ECALE has been used to grow mainly II-VI and III-V compounds. A thorough review of ECALE research has been published by Stickney.144 A summary of the materials deposited using ECALE are given in Table 8.4, with a more detailed discussion for a few select examples given below. 

Every single regeneration problem has to be analysed individually, however, the following case study demonstrates how a selection of separation techniques, extraction and phase separation, can successfully be applied to regenerate a spent ionic liquid based electrolyte satisfactorily. As a case study the electrolyte 1-butyl-1-methylpyrrolidinium bis(trifluoromethanesulfonyl)amide ([BMP]Tf2N) was chosen, which is used for electrodeposition of aluminum as described in the literature [137, 138],... 

Separation procedures are based on the principles of volatilization, liquid-liquid distribution, adsorption, diffusion, chromatography, ion exchange, electrophoresis, precipitation, coprecipitation, and electrodeposition. In all of these, radio-tracers provide the best tool for methodological investigations, determination of equilibrium constants, kinetic data, and optimization of applied analytical data (yield, interference levels, etc.) [54], Use of radiotracers in complex multielement separation schemes is reviewed in [4], [17], [20]. [41], [54], radiochromatography is reviewed in [551. [61], [93], 197],... 

As described above, it is worthwhile for practical use to evaluate the material flow from all recovery processes such as pretreatment, wet separation, and electrodeposition using ILs. The material flow for aU of recovery processes was displayed in Fig. 6.31, and the recovery target on this material flow was based on the oxidized Nd-Fe-B magnet wastes after roasting process. 

Analogous to traditional ILs, deep eutectic solvents have been successfiilly applied in electrochemistry as electrolytes for i) electrodeposition of metals, ii) dyes-sensitized solar cells,iii) electropolishing of metals, " and iv) metal separations. In this section we will focus our attention on the electrodeposition of metals using different ChCl-based eutectic mixtures (ChCl/Urea and ChCl/EG). 

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