Chlorocomplexes, anionic

The electrochemical technique gave the possibility of obtain the to-acetonitrilc adduct of the tetrachlorides and bromides, except in those cases where gram quantities of tetra-ethylammonium halide were present when the appropriate anionic halogen complexes were obtained. Thionyl chloride proved to be the most satisfactory solvent for the preparation of the anionic chlorocomplexes. 

In aqueous effluents with high concentration of hydrochloric acid, different iron and zinc chlorocomplex species have been reported in the open literature. Fe + and Fe form only cationic or neutral compounds such as FeCF and FeCl2 and FeCF" and FeCla, while Zn + in the presence of chloride usually forms anionic chlorocomplexes that are selectively extracted with the solvating reagents typically employed in the extraction of anionic compounds. ... 

Solvating reagents can also extract bulky anions, e.g., Cr04, Mo04, and anionic chlorocomplexes, by means of the hydration mechanism. For example. 

Figure 28.4 The anions of the chlorocomplex of stoichiometry, CsAuCl3, showing linearly coordinated Au and (4 + 2) tetragonally distorted, octahedral Au , i.e. Cs2[Au Cl2][Au CLt]-...

Platinum group metals Mixtures of anionic or neutral chlorocomplexes Extractants either anion exchangers (e.g., long-chain amino acids) or ligands (e.g., alkyl sulfides)... 

In the case of basic ionic liquids that contain AICI3 at less than 50 mol%, the metal salt acts as a Lewis acid by accepting the chloride anions in the ionic liquids to form a chlorocomplex anion ... 

Polymeric chlorocomplex anions are also known for some metals. Since the electrodeposition of A1 does not occur within the electrochemical potential window of known alkylated imidazolium and pyridinium cations under the basic condition of room temperature, an electrodeposit of the pure metal can be obtained. 

The electrodeposition of indium. In, has been reported in a basic DMPICl—AICI3 ionic liquid [24]. Indium trichloride, InCl3, dissolves in the basic ionic liquid and forms a trivalent indium chlorocomplex anion, InClj, which can be reduced to metallic In by a three-electron transfer reaction ... 

Metallic thallium, Tl, can be electrodeposited in a basic EMICI-AICI3 ionic liquid [25]. It is possible to dissolve thallium trichloride, TICI3, to form a trivalent thallium chlorocomplex anion, TlClg , which is reducible to a monovalent thallium chlorocomplex anion, TlCl ... 

The experimental value is reported as 0.389 V. On the other hand, an trivalent antimony chlorocomplex anions, SbCl4, is dominant in the basic ionic liquid and is also reducible to metallic Sb at more negative potential ... 

In a neutral buffered EMICI-AICI3 ionic liquid, the anodic oxidation of Ni metal results in forming NiCl2, which is insoluble in this ionic liquid [37]. In the case of a basic BPCI-AICI3 ionic liquid, NiCl2 dissolves and forms a divalent nickel chlorocomplex anion, NiCl , which cannot be reduced to metallic Ni [46]. 

The electrodeposition of cadmium, Cd, is possible in the basic and neutral EMICI-AICI3 ionic liquids [56, 58]. In the basic ionic liquid, cadmium dichloride, CdCl2, dissolves and forms a divalent cadmium chlorocomplex anion, CdCl [69], which is reducible to metallic Cd at around — 1.2 V. In the case of a neutral buffered ionic liquid, the electrodeposition of Cd is observed at around —1.0 V, which is slightly positive than in the basic ionic liquid probably caused by the formation of more reducible species, CdCl3. ... 

The formal potentials of Hg /Hg and Hg /Hg are reported as 1.21 and 1.093 V, respectively. In case of the basic ionic liquid, HgCl2 dissolves and forms a divalent mercury chlorocomplex anion, HgCl . The reduction of HgCl results in the deposition of metallic Hg ... 

Bismuth Steels Dowex 1-X8 anion exchange resin UV—Vis 0.001 mg L-1 (injectate) Flow injection system analyte sorption as chlorocomplex [493]... 

For the determination of Ir in aerosol particulate samples, Heller-Zeisler et al. (2000) compared three methods, INAA, RNAA, and thermal-ionization mass spectrometry. In the RNAA procedure, Ir was separated from the digested sample on an anion-exchange resin as a chlorocomplex. The sensitivities of INAA and RNAA were comparable, i.e., 60-100 fg and both of them were superior to mass spectroscopy. 

When Au or Pt are determined by RNAA, the Au and Au indicator radionuclides have to be separated, e.g., by retention as a chlorocomplex on an anion-exchange resin, by precipitation as a reduced metal, by electroplating, or by solvent extraction. For samples containing both Au and Pt, it has to be kept in mind that Au is formed from both elements (Zeisler and Greenberg 1982). 

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