The mechanism of extraction of iron(III) from 6 M hydrochloric acid by long chain amines in chloroform

1983 ◽  
Vol 36 (7) ◽  
pp. 1319 ◽  
Author(s):  
MZ Ilic ◽  
RW Cattrall ◽  
DE Davey

The mechanism of transfer of FellI between 6.0 M HCl and five amine chlorides in chloroform has been studied by means of the single-drop technique. It is suggested that the (1,1) complex forms at the interface by fast ion-exchange and that the rate determining step involves the replacement of the complex at the interface by one molecule of reagent monomer from the bulk organic phase. Additional heterogeneous aggregates are formed in the bulk organic phase by fast reactions with reagent monomer. Support for this mechanism is obtained through the excellent agreement between the extraction equilibrium constants calculated from the rate data for the (1,1) complexes and the values obtained previously by two phase titration studies.

1982 ◽  
Vol 35 (6) ◽  
pp. 1095 ◽  
Author(s):  
H Daud ◽  
RW Cattrall

The mechanism of the transfer of zinc(11) between 1.0 M HCl, 6.0 M HCl and 6.0 M LiCl and methyltrioctylammonium chloride in chloroform has been studied by using the single-drop technique. It is suggested that interfacial complexes are formed by fast ion-exchange reactions and that the rate-determining step, in the case of 1.0 M HCl and 6.0 M LiCl, involves the replacement at the interface of the complex R2ZnCl4 by two molecules of reagent from the bulk organic phase. For 6.0 M HCl the rate-determining step is the replacement of the interfacial complex RHZnCl4 by one molecule of reagent from the bulk organic phase. Support for this mechanism is obtained by comparing the extraction equilibrium constants for the complex R2ZnCl4 for 1.0 M HCl and 6.0 M LiCl from previous with the values calculated from the rate data. Interfacial tension measurements have shown that the interface is saturated with reagent over the full range of concentrations studied.


1982 ◽  
Vol 35 (11) ◽  
pp. 2345 ◽  
Author(s):  
R Paimin ◽  
RW Cattrall

The extraction of cobalt(II) by Aliquat 336R from 7 M lithium chloride solutions involves two species from the aqueous phase, COCl42 and CoCl3-, with the former being the predominant one. The equilibrium constants for the formation of the extracted complexes (R3MeN+)2 CoCl42- and R3MeN+CoCI3- are: logKll 5.01 and logK12 9.55. From the results of experiments by means of the single-drop technique, a mechanism is proposed based on the formation of interfacial complexes by fast ion-exchange with a rate-determining step which involves the replacement at the interface of the complex (R3MeN+)2 COCl42- by two molar proportions of reagent from the bulk organic phase.


1986 ◽  
Vol 39 (7) ◽  
pp. 987 ◽  
Author(s):  
R Paimin ◽  
RW Cattrall

A study is reported of the extraction of cobalt(II) from oxalate solutions by Aliquat 336 in chloroform. Equilibrium studies by two-phase titration show that the predominant organic-phase complex has the formula [(R3MeN)2Co(C2O4)2]. It is proposed that this species is formed by extraction of the anionic complex Co(C2O4)22- involving interfacial reactions. There is evidence for the formation of a small amount of the complex [(R3MeN)4Co(C2O4)3]. The extraction mechanism proposed is based on a study with the single-drop technique, and is supported by interfacial tension measurements and measurements with a stirred cell of constant interfacial area.


2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Nazan Karapinar ◽  
Emin Karapinar ◽  
Emine Ozcan

Liquid-liquid extraction of various alkalis (Li+, Na+, K+, and Cs+), transition metals (Co2+, Ni2+, Cu2+, Zn2+, Cd2+, and Hg2+), and Pb2+cations with phenylglyoxime (L1), p-tolylglyoxime (L2),N′-(4′-Benzo[15-crown-5])phenylaminoglyoxime (L3), andN′-(4′-Benzo[15-crown-5])-p-tolylaminoglyoxime (L4) from the aqueous phase into the organic phase was carried out. For comparison, the corresponding two glyoximes and their macrocyclic glyoxime ether derivatives were also examined. Crown ether groups having ligands (L3,L4) carry especially Na+cation from aqueous phase to organic phase. The extraction equilibrium constants (Kex) for complexes of ligands with Cu2+and Hg2+metal picrates between dichloromethane and water have been determined at 25°C. The values of the extraction constants (logKex) were determined to be 12.27, 13.37, 12.94, and 12.39 for Cu2+and 10.29, 10.62, 11.53, and 11.97 for Hg2+with L1–L4, respectively.


1984 ◽  
Vol 37 (3) ◽  
pp. 489 ◽  
Author(s):  
MZ Ilic ◽  
RW Cattrall

Two-phase titration studies demonstrate a strong tendency for the formation of heterogeneous aggregates in the extraction of iron(III) from 6 M HCl by primary, secondary and tertiary amine hydrochlorides in chloroform. The stoichiometries of the extracted complexes are identified, and their extraction equilibrium constants are reported. The importance of the reagent monomer in the extraction process is discussed.


1985 ◽  
Vol 50 (3) ◽  
pp. 581-599 ◽  
Author(s):  
Petr Vaňura ◽  
Emanuel Makrlík

Extraction of microamounts of Sr2+ and Ba2+ (henceforth M2+) from the aqueous solutions of perchloric acid (0.0125-1.02 mol/l) by means of the nitrobenzene solutions of dicarbolide (0.004-0.05 mol/l of H+{Co(C2B9H11)2}-) was studied in the presence of monoglyme (only Ba2+), diglyme, triglyme, and tetraglyme (CH3O-(CH2-CH2O)nCH3, where n = 1, 2, 3, 4). The distribution of glyme betweeen the aqueous and organic phases, the extraction of the protonized glyme molecule HL+ together with the extraction of M2+ ion and of the glyme complex with the M2+ ion, i.e., ML2+ (where L is the molecule of glyme), were found to be the dominating reactions in the systems under study. In the systems with tri- and tetraglymes the extraction of H+ and M2+ ions solvated with two glyme molecules, i.e., the formation of HL2+ and ML22+ species, can probably play a minor role. The values of the respective equilibrium constants, of the stability constants of complexes formed in the organic phase, and the theoretical separation factors αBa/Sr were determined. The effect of the ligand structure on the values of extraction and stability constants in the organic phase is discussed.


1986 ◽  
Vol 51 (3) ◽  
pp. 498-515 ◽  
Author(s):  
Emanuel Makrlík ◽  
Petr Vaňura

Extraction of Eu3+ and Ce3+ microamounts from 0.1-0.4M perchloric acid by the nitrobenzene solution of dicarbolide H+[Co(C2B9H11)2]- in the presence of polyethylene glycols (Mr = 200, 300, 400) has been studied. The equilibrium data and the typical maxima on the dependence of the metal distribution ratio on the total analytical concentration of polyethylene glycol in the system can be explained assuming that the species ML3+org, ML3+2org, ML3+3org, MLH2+-1org, and HL+org (where M3+ = Eu3+, Ce3+; L = polyethylene glycol) are extracted into the organic phase. The values of extraction and equilibrium constants in the organic phase were determined and the effect of the polyethylene glycol molecular weight on the equilibrium constants and on the abundances of individual species in the organic phase is discussed. It has been found that the addition of polyethylene glycol to the acid - nitrobezene - dicarbolide system increases the values of the separation factors αCe/Eu.


2019 ◽  
Vol 34 (S1) ◽  
pp. S8-S13
Author(s):  
T. Konya ◽  
Y. Shiramata ◽  
T. Nakamura

Structural variation of LiMn1.5Ni0.5O4 spinel cathode during the Li+ extraction/insertion reaction was studied using operando X-ray diffraction. It was found that the reaction in the voltage range from 3.5 to 4.9 V consisted of two consecutive two-phase reactions, where three spinel phases of LiMn1.5Ni0.5O4, Li0.5Mn1.5Ni0.5O4 and Mn1.5Ni0.5O4 were identified and the lattice volume change in the whole reaction was evaluated as 6%. The reactions were symmetric and reversible under low-current conditions, but some asymmetries were detected during high current operation. Furthermore, a two-phase reaction between cubic and tetragonal phases was observed in the low-voltage reaction at 2.1–3.5 V, where the lattice volume change was approximately 4.9%. The rate-determining step was discussed based on these operando results.


Separations ◽  
2021 ◽  
Vol 8 (11) ◽  
pp. 211
Author(s):  
Keisuke Ohto ◽  
Nako Fuchiwaki ◽  
Hiroaki Furugou ◽  
Shintaro Morisada ◽  
Hidetaka Kawakita ◽  
...  

We prepared acetic acid derivatives using three different frameworks, calix[4]arene, alkenyltrimethylol, and trihydroxytriphenylmethane, which differ in the number and size of their coordination sites. We further investigated the extraction properties for aluminum group metal ions. All three extraction reagents exhibited increased extraction compared with the corresponding monomeric compounds, owing to structural effects. The extraction reaction and extraction equilibrium constants were determined using a slope analysis. Their extraction abilities, separation efficiencies, and potential coordination modes are discussed using the extraction equilibrium constants, half-pH values, and spectroscopic data. The calix[4]arene and trihydroxytriphenylmethane derivatives demonstrated allosteric co-extraction of indium ions (In3+) with an unexpected stoichiometry of 1:2.


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