Wasserumsatz und Stoffbewegungen

The Electrorefinement of Indium Through an Aluminum Alkyl Complex Electrolyte

“…3[AI(C2Hs)4] e + A1 :) 4Al(C~Hs)3 + 3e e [6] The formation of ethyl radicals in the anodic step, as assumed in Eq. [3], is a proven experimental fact and leads, in the case of inert metal anode, to the formation of the disproportionation products ethane and ethylene, as previously reported (9). For the cathodic reaction 3AI(C2Hs)2 ~ + 3e e .…”

“…Figure 3 shows the '~F-NMR spectra for molar ratio of toluene to NaF to Al(C2Hs)3 = 3:l:m solutions with (a) m = 2, (b) m = 2, (c) m = 2.5, and (d) m = 4. A single peak at 4~ = 183 ppm is observed for the m = 1 solution and is associated with the 1:1 complex Na[FAI(C~H.~):~] reported previously (1)(2)(3)5). For the m = 2 solution, a predominant peak at 172 ppm and a weak second peak at 166 ppm are recorded.…”

“…The ability of aluminum alkyl compounds, A1R3, to form complex electrolytes with alkali halides was discovered in 1955 by Ziegler et al (1,2), who recognized the potential of these electrolytes for the electrorefinement of aluminum (3). In subsequent patent applications, the replacement of the alkali halides by quaternary ammonium halides (4) and the extension of the electrorefinement to other Group IIIA metals, (4) and Group IIB and Group IVA-VIA elements (5) have been disclosed.…”

“…: ) A1 + 2Al(C2Hs)3 [7] Since a replacement of the A1 anode by an In anode leads to the chemical dissolution of In according to Eq. [8] In + 3C~H~ > In(C2Hs)3 Consequently, upon electrolysis under galvanostatic conditions, the initially pure aluminum complex electrolyte becomes enriched in triethylindium, which, according to the equilibrium 2In(C2Hs)3 : "In(C2H~h e + In(C2H~)2 e [10] is coupled to net cathodic reaction 3In(C~H~)~ e + 3e e ) In + 2In(C2Hs)3 [11] This suggests the possibility of In deposition from an initially pure A1 complex electrolyte, which has been verified previously (9) and has been explored here in more detail.…”