studies in the solvent extraction of some thallium(I) chelates

Studies of the extraction of thallium(I) from aqueous solution into chloroform or MIBK using 6 reagents have been made. Reagent concentration, pH variation, and the addition of adductforming agents to the organic phase have all been investigated. Association constants and distribution coefficients for several of the better reagents have been determined. Theoretical interpretations have permitted the identification, of participating species and the calculation of equilibrium constants in several cases.     

Solvent extraction studies of cobalt(II) by capric acid from sodium sulfate solution

The extraction of cobalt(II) from sulfate medium of ionic strength 0.33?mol dm^?3 by capric acid dissolved in chloroform has been carried out at 25°C. By using the slope analysis method, the stoichiometry of the organometallic complex extracted was determined. Cobalt(II) complex exists as a mononuclear species CoL₂.2HL in the lower concentration region of capric acid and a binuclear ones (CoL₂.2HL)₂ in the higher concentration region. Extraction constants for each species were given. UV–visible and FTIR spectroscopy have also been used for the investigation of the extractant and their complexes. Electronic spectrum of cobalt(II) caprate species indicates the octahedral structure.     

The solvent extraction of some thallium(I) chelates

Fourteen different chelating reagents have been investigated, as possible extradants for radioiabelled 10^-6M thallium(I) from aqueous solutions into chloroform. The data have beun analyzed theoretically to identify the predominant species involved and to estimate association and distribution constanta.     

The solvent extraction of some thallium(I) chelates

Studies of the extraction of thallium (I) from aqueous solution into an immiscible organic solvent have been made using 71 chelating reagent-solvent pairs involving 16 reagents and 17 solvents. The data have been analyzed to identify the predominant species involved, and association and partition constants have been estimated in many cases, The best extraction systems seem to be those involving 3phenylpropylxanthate and chloroform, chlorobenzene or methylene chloride.     

Extraction liquide-liquide et chromatographie en phase gazeuse de chelates mixtes de nickel(ii) et cobalt(ii) : complexes metal-thenoyltrifluoroacetone-diethylamine

The effect of diethylamine (S) in the extraction of nickel and cobalt thenoyl-trifluoroacetonates (MT₂) was studied. The results showed that quantitative extraction may be carried out, with formation of a single species MT₂S₂, which is more stable with cobalt than with nickel. An aqueous solution of these two cations may be analysed by liquid-liquid extraction and gas chromatography of the organic phase.

Zusammenfassung

Der Einfluss von Diäthylamin (S) bei der Extraktion von Nickel- und Kobaltthenoyltrifluoracetonat (MT₂) wurde untersucht. Die Ergebnisse zeigten, dass eine quantitative Extraktion unter Bildung einer einzigen Spezies MT₂S₂ ausgeführt werden kann, wobei die Verbindung mit Kobalt stabiler als die mit Nickel ist. Eine wässrige Lösung dieser beiden Kationen kann durch Flüssig-Flüssig-Extraktion und durch Gaschromatographie der organischen Phase analysiert werden.     

Kinetic Analyis of TG Data XXXV. Spectroscopic and thermal studies of some cobalt(III) chelates with ethylenediamine

A number of 30 [Co(en)₃ ]Y₃ , [Co(en)₂ X₂ ]Y and [Co(en)₂ X(amine)]Y₂ type complexes (X =Cl, Br; Y =Cl, Br, I, NCO, NCS, NO₃ , ClO₄ , etc.; amine =aromatic and alkylamines) were obtained from trans-[Co(en)₂ Cl₂ ]Cl by double decomposition and by substitution reactions, respectively. The structure of the complexes was proved by means of far and middle FTIR spectra. The thermal decomposition was studied by TG, DTA and DSC measurements. Mass spectra were also recorded. In the case of [Co(en)₃ ]Y₃ complexes the nitrate, perchlorate and dimesoperiodates decompose suddenly, frequently explosion like. The halides and thiocyanates seem to substitute an ethylenediamine ligand, yielding a rather unstable intermediate. The pyrolysis of [Co(en)₂ X₂ ]Y type derivatives yields no relatively stable intermediates, but the decomposition temperatures may be correlated with the nature of Y and with the cis or trans configuration of the compound. With the [Co(en)₂ X(amine)]Y₂ type complexes one observes the formation of [Co(en)₂ XY]Y as intermediate product. From the TG curves kinetic parameters were derived for some dehydration and deamination processes, by using the nomogram method. The validity of a non-linear kinetic compensation law was observed. This revised version was published online in July 2006 with corrections to the Cover Date.     

Solvent extraction study of cobalt(II) with 8-mercaptoquinoline

Equilibrium distribution coefficients have been determined for the extraction of cobalt(II) with 8-mercaptoquinoline as a function of pH and reagent concentraton at ambient temperature. The extractable complex is a diadduct, i. e. two molecules of the reagent are coordinated to the cobalt(II) chelate. The adduct formation constant in chloroform and the overall formation constant in the aqueous phase have been determined. Pyridine and its methyl derivatives were found to enhance the extraction of Co(II) into chloroform in the presence of 8-mercaptoquinoline. From the extraction equilibrium data, the adduct formation constants of 12 chelate to nitrogen base adducts were evaluated. The special role of steric factors is discussed.     

Solvent extraction separation of cobalt(II) with hexaacetatocalix(6)arene

A new method is proposed for the solvent extraction separation of cobalt(II) with hexaacetatocalix(6)arene in toluene. Cobalt(II) was extracted at pH 7.4 with 10 x 10(-4) M hexaacetocalix(6)arene, stripped with 2 M nitric acid, and determined spectrophotometrically at 500 nm as its complex with nitroso-R-salt. Cobalt was separated from any associated elements. The method was extended to the analysis of cobalt(II) in real samples such as vitamin B-12.     

Copper(ii), cobalt(ii), manganese(ii) and nickel(ii) bis(hexafluoroacetylacetonate) complexes with N-vinylimidazole

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Solvent extraction studies of cobalt in aqueous thiocyanate solutions using Aliquat-336

Cobalt ions in aqueous thiocyanate solution react with Aliquat-336-xylene solution to form anion-association complex which is easily extracted into the organic phase. A typical extraction procedure involves extracting a solution which is 10 ppm in cobalt and 0.06 M,

5. Stripping of Cobalt from 2% Aliquat-336-Xylene Solutions

     

14.

Homo- and heterometallic trinuclear nickel(ii) and cobalt(ii) pivalate complexes     

Aleksandrov  G. G.  Fomina  I. G.  Sidorov  A. A.  Mikhailova  T. B.  Zhilov  V. I.  Ikorskii  V. N.  Novotortsev  V. M.  Eremenko  I. L.  Moiseev  I. I. 《Russian Chemical Bulletin》2004,53(6):1200-1207

The reaction of the dinuclear complex Co₂(bpy)₂(OOCBu^t)₄ with the tetranuclear complex Ni₄(₃-OH)₂(OOCBu^t)₆(EtOH)₆ afforded the trinuclear heterometallic complex M₃(bpy)₂(₃-OH)(-OOCBu^t)₄(OOCBu^t) (6) (M = Ni, Co; Ni : Co = 1.2 : 1) in which two metal atoms are in an octahedral environment and one metal atom is in a tetrahedral environment. The reaction of 2,2"-bipyridine with Co₄(₃-OH)₂(OOCBu^t)₆(HOEt)₆ (reagent ratio was 2 : 1) or the reaction of bpy with Co₈(₄-O)₂( _n -OOCBu^t)₁₂ (reagent ratio was 4 : 1) produced a homometallic analog of 6, viz., the trinuclear cluster Co₃(bpy)₂(₃-OH)(-OOCBu^t)₄(OOCBu^t) (8). The reaction of 1,10-phenanthroline (phen) with the [Co(OH) _n (OOCBu^t)_2–n ] _x polymer gave the analogous trinuclear cluster (phen)₂Co₃(₃-OH)(₂-OOCBu^t)₄(¹-OOCBu^t). Compounds 6 and 8 exhibit antiferromagnetic spin-spin exchange interactions.     

15.

Solvent extraction of cobalt(II) with 8-quinolinol and its analogues in the presence of some heterocyclic nitrogen bases     

Kashinath S. Bhatki  Arvind T. Rane 《Transition Metal Chemistry》1978,3(1):181-184

Summary Pyridine and its 2-methyl, 2,4-dimethyl and 2,4,6-trimethyl derivatives enhance the extraction of cobalt(II) into chloroform in the presence of 8-quinolinol and its 2-methyl, 4-methyl, 5-chloro and 5-nitro analogues. Adduct formation constants were determined for the cobalt(II) chelates, which formed diadducts with the pyridine bases. The special role of steric factors is discussed. The results are consistent with Lewis acid-base concepts.     

16.

Coordination behaviour of 2-halo-1,3,4-thiadiazoles towards cobalt(ii) and nickel(ii)     

Adriano Benedetti  Pier G. De Benedetti  Antonio C. Fabretti  Giancarlo Franchini  Corrado Gatti 《Transition Metal Chemistry》1984,9(12):457-460

Summary A series of cobalt(II) and nickel(II) 2-X-1,3,4-thiadiazole complexes (X=Cl or Br) were investigated by electronic, n.m.r., Raman and i.r. spectroscopy, and by thermogravimetric analyses, magnetic moments and conductivity measurements.The complexes havepseudo-tetrahedral or pseudo-octa-hedral stereochemistries with MN₂X₂ (X=Cl or Br), MN₄X₂ (X=Cl, Br or O) or MN₃O₃ chromophores.The ligands are mono- or bi-dentate without involving the sulphur atom. Surprisingly, the chloro-derivative ligand seems to be more nucleophilic than the bromo-analogue.The computed (CNDO/2) molecular orbital indices for the uncomplexed ligands indicate that the coordination sites are the nitrogen atoms.In connection with our previous work⁽¹⁾ on the coordination ability of heterocyclic ligands with interesting biological^(2,3) and pharmaceutical⁽⁴⁾ properties and containing endocyclic nitrogen and sulphur donor atoms, we have considered the 1,3,4-thiadiazole ring, which is the main framework of a very important class of diuretic drugs, the sulphonamide inhibitors⁽⁵⁾ of the zinc m tallo-enzyme carbonic anhydrase.In this study we have investigated the coordination behaviour of the 2-chloro-1,3,4-thiadiazole(ctz) and the 2-bromo-1,3,4-thiadiazole (btz).     

17.

Synthesis and characterization of triethanolamine complexes with cobalt(ii) and zinc(ii) cinnamates     

《Mendeleev Communications》2020,30(5):639-641

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18.

Solvent extraction of cobalt(II) di(2-ethylhexyl)dithiophosphate adducts with oxygen donor ligands     

《Journal of Inorganic and Nuclear Chemistry》1979,41(5):767-769

     

19.

Investigation of the extraction of some copper(II) chelates using isotope64Cu     

E. E. Rakovskii  O. M. Petrukhin  V. I. Severin 《Journal of Radioanalytical and Nuclear Chemistry》1970,4(2):207-214

The extraction of copper(II) 8-hydroxyquinolinate, 5,7-dichloro-8-hydroxyquinolinate and 2-thenoyltrifluoroacetonate was investigated and the stability constants and distribution constants of the complexes were determined. The dependence of thepH values for 50% extraction and of the distribution constants of the copper complexes on the dissociation constants and distribution constants of the corresponding agents are discussed.     

20.

Solvent extraction of some incapacitating agents     

O. Navrátil  Z. Kobliha  E. Halámek 《Journal of Radioanalytical and Nuclear Chemistry》2004,262(2):429-432

Five different incapacitating agents have been studied as ionic associates using solvent extraction. The water phase contained 0.1-0.01M HCl, the organic phase was chloroform. The distribution of appropriate ionic associates was established by means of dicarbollylcobaltate anion labeled with ⁶⁰Co. This revised version was published online in July 2006 with corrections to the Cover Date.     

Strippant	Cobalt stripped (%)
Na2S (M) 1.0	18.3
2.0	10.7
Na2SO3 (M) 0.1	10.7
0.5	49.6
1.0	52.9
EDA (%) 2.5	76.6
NaOH (M) 0.1	4.1
0.5	74.1
1.0	90.8
2.0	76.8
NH4OH (M) 0.1	24.1
0.5	91.8
1.0	97.5
2.0	99.9
EDTA (M) 0.02	>99.9
0.05	>99.9
0.1	>99.9
EDTA (%) 0.1	>99.9
0.5	>99.9
1.0	>99.9

Homo- and heterometallic trinuclear nickel(ii) and cobalt(ii) pivalate complexes

The reaction of the dinuclear complex Co₂(bpy)₂(OOCBu^t)₄ with the tetranuclear complex Ni₄(₃-OH)₂(OOCBu^t)₆(EtOH)₆ afforded the trinuclear heterometallic complex M₃(bpy)₂(₃-OH)(-OOCBu^t)₄(OOCBu^t) (6) (M = Ni, Co; Ni : Co = 1.2 : 1) in which two metal atoms are in an octahedral environment and one metal atom is in a tetrahedral environment. The reaction of 2,2"-bipyridine with Co₄(₃-OH)₂(OOCBu^t)₆(HOEt)₆ (reagent ratio was 2 : 1) or the reaction of bpy with Co₈(₄-O)₂( _n -OOCBu^t)₁₂ (reagent ratio was 4 : 1) produced a homometallic analog of 6, viz., the trinuclear cluster Co₃(bpy)₂(₃-OH)(-OOCBu^t)₄(OOCBu^t) (8). The reaction of 1,10-phenanthroline (phen) with the [Co(OH) _n (OOCBu^t)_2–n ] _x polymer gave the analogous trinuclear cluster (phen)₂Co₃(₃-OH)(₂-OOCBu^t)₄(¹-OOCBu^t). Compounds 6 and 8 exhibit antiferromagnetic spin-spin exchange interactions.     

Solvent extraction of cobalt(II) with 8-quinolinol and its analogues in the presence of some heterocyclic nitrogen bases

Summary Pyridine and its 2-methyl, 2,4-dimethyl and 2,4,6-trimethyl derivatives enhance the extraction of cobalt(II) into chloroform in the presence of 8-quinolinol and its 2-methyl, 4-methyl, 5-chloro and 5-nitro analogues. Adduct formation constants were determined for the cobalt(II) chelates, which formed diadducts with the pyridine bases. The special role of steric factors is discussed. The results are consistent with Lewis acid-base concepts.     

Coordination behaviour of 2-halo-1,3,4-thiadiazoles towards cobalt(ii) and nickel(ii)

Summary A series of cobalt(II) and nickel(II) 2-X-1,3,4-thiadiazole complexes (X=Cl or Br) were investigated by electronic, n.m.r., Raman and i.r. spectroscopy, and by thermogravimetric analyses, magnetic moments and conductivity measurements.The complexes havepseudo-tetrahedral or pseudo-octa-hedral stereochemistries with MN₂X₂ (X=Cl or Br), MN₄X₂ (X=Cl, Br or O) or MN₃O₃ chromophores.The ligands are mono- or bi-dentate without involving the sulphur atom. Surprisingly, the chloro-derivative ligand seems to be more nucleophilic than the bromo-analogue.The computed (CNDO/2) molecular orbital indices for the uncomplexed ligands indicate that the coordination sites are the nitrogen atoms.In connection with our previous work⁽¹⁾ on the coordination ability of heterocyclic ligands with interesting biological^(2,3) and pharmaceutical⁽⁴⁾ properties and containing endocyclic nitrogen and sulphur donor atoms, we have considered the 1,3,4-thiadiazole ring, which is the main framework of a very important class of diuretic drugs, the sulphonamide inhibitors⁽⁵⁾ of the zinc m tallo-enzyme carbonic anhydrase.In this study we have investigated the coordination behaviour of the 2-chloro-1,3,4-thiadiazole(ctz) and the 2-bromo-1,3,4-thiadiazole (btz).     

Synthesis and characterization of triethanolamine complexes with cobalt(ii) and zinc(ii) cinnamates

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Investigation of the extraction of some copper(II) chelates using isotope64Cu

The extraction of copper(II) 8-hydroxyquinolinate, 5,7-dichloro-8-hydroxyquinolinate and 2-thenoyltrifluoroacetonate was investigated and the stability constants and distribution constants of the complexes were determined. The dependence of thepH values for 50% extraction and of the distribution constants of the copper complexes on the dissociation constants and distribution constants of the corresponding agents are discussed.     

Solvent extraction of some incapacitating agents

Five different incapacitating agents have been studied as ionic associates using solvent extraction. The water phase contained 0.1-0.01M HCl, the organic phase was chloroform. The distribution of appropriate ionic associates was established by means of dicarbollylcobaltate anion labeled with ⁶⁰Co. This revised version was published online in July 2006 with corrections to the Cover Date.