Alkali metal ions separation

Table 6. Maximum molar ratios of transported alkali metal ions to crown ether carrier for several separation techniques...

Except for sensor applications, the intercalation of alkali metal ions in metal hexacyanoferrates was used for adsorption and separation of cesium ions from different aqueous solutions with Prussian blue [43,44] and cupric hexacyanoferrate [45,46],... 

T. Ikeshoji, Separation of alkali-metal ions by intercalation into a Prussian blue electrode. J. Electrochem. Soc. 133, 2108-2109 (1986). 

Kit for the separation of low-molecular mass organic cations like alkali metal ions, alkaline earth metal ions, and alkyl amines. Indirect UV detection is applied. 

The complexes of alkali metal ions and of their salts described in paras. II—V may also be considered as lattice compounds because they do not necessarily persist in solution. Where the charge on the cation is neutralised by a small anion to give a salt, the solid may contain ion pairs coordinated by the additional ligand molecules, or the ions may be separated by the ligands, which usually form hydrogen bonds to the anion. When the cation is neutralised by a polydentate anion, the co-... 

Complex chlorides of Ce4+ may be prepared by dissolution of cerium(IV) hydroxide in methanolic hydrochloric acid followed by addition of a base B, giving (BH)2[CeCl6]. (NH4)2CeCl6 can be used as a selective precipitant for Cs+ ions in presence of other alkali metals, with separation coefficients ranging from 5300 (Na) to 60 (Rb).718... 

As the carbon black structure may be reduced by the presence of alkali metal ions in the reaction zone [4.11], alkali metal salts, preferably aqueous solutions of potassium hydroxide or potassium chloride, are often added to the make oil in the oil injector. Alternatively, the additives may be sprayed separately into the combustion chamber. In special cases, other additives, e.g., alkaline-earth metal compounds which increase the specific surface area are introduced in a similar manner. 

Group V Na+, K+, and Mg2+ The only ions remaining in solution at this point are those whose chlorides, sulfides, and carbonates are soluble under conditions of the previous reactions. Magnesium ion is separated and identified by addition of a solution of (NH4)2HP04 if Mg2+ is present, a white precipitate of Mg(NH4)P04 forms. The alkali metal ions are usually identified by the characteristic colors that they impart to a Bunsen flame (Figure 16.18). 

Kimura, K., Hayata, E., and Shono, T. (1984) Convenient, efficient crown ether-containing stationary phases for chromatographic separation of alkali metal ions dynamic coating of highly lipophilic crown ethers on octadecylsilanized silica, Chem. Commun., 271-272. 

This behavior has allowed the development of solvent-extraction procedures for alkali metal ions. Thus not only can the trioctylphosphine oxide adduct in Li[PhC(0)CHC(0)Ph][OP(octyl)3]2 be extracted from aqueous solutions into p-xylene, but this process can also be used to separate lithium from other alkali metal ions. Even Cs+ can be extracted from aqueous solutions by l,l,l-trifluoro-3-(2 thenoyl) acetone (TTA) in MeN02—hydrocarbons, and all of the M+ ions can be extracted into chloroform by crown ethers, in a manner that depends upon the associated anions.33... 

The interlayer separation directly depends on the number of water molecules present between the layers. In the anhydrous phases ZrM(P04)2 (M = Mg, Ca, Sr, or Ba) and the half exchanged phases ZrHM(P04)2 (M = Li, Na, K, Rb, or Cs) the interlayer separation is independent of cation size, indicating that the interlayer cavity, which contains one water molecule in the unexchanged compound, is sufficiently large to accommodate a single cation. In contrast, in the fully exchanged alkali metal ion compositions, the interlayer separation increases with increasing cation radius. 

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