Extraction of strontium and barium by nitrobenzene solution of dicarbolide in the presence of polyethylene glycols

1982 ◽  
Vol 47 (5) ◽  
pp. 1444-1464 ◽  
Author(s):  
Petr Vaňura ◽  
Emanuel Makrlík ◽  
Jiří Rais ◽  
Miroslav Kyrš
Keyword(s):  
Polyethylene Glycol ◽  
Organic Phase ◽  
Equilibrium Constants ◽  
Polyethylene Glycols ◽  
Hydration Numbers ◽  
Nitrobenzene Solution ◽  
Karl Fischer Titration ◽  
Peg 400 ◽  
Extraction Constants

Extraction of microamounts of Sr2+ and Ba2+ from 0.2-1.0M-HClO4 by the nitrobenzene solutions of dicarbolide H+[Co(C2B9H11)2]- in the presence of polyethylene glycols (PEG) (Mr = 200, 300, 400) has been investigated. It has been found that the extraction of the protonized polyethylene glycol molecule (H+ + L ##e HL+, where the bar denotes species present in the organic phase) and the extraction of the complex between the extracted ion and polyethylene glycol, i.e., M2+ +L + 2 H+ ##e ML2+ + 2 H+, are the predominant reactions in this system. The respective equilibrium constants have been determined. The hydration numbers of HL+ and ML2+ ions in the organic phase have been obtained from the determination of water content by Karl Fischer titration method. The extraction constants and stability constants in the organic phase increase in the sequence H+ < Sr2+ < Ba2+ and PEG 200 < PEG 300 < PEG 400, while the hydration numbers decrease in the same sequence. Correlations between the hydration numbers and the extraction constants for these cations have been found.

Europium and cerium extraction by the nitrobenzene solution of dicarbolide in the presence of polyethylene glycols

1986 ◽  
Vol 51 (3) ◽  
pp. 498-515 ◽  
Author(s):  
Emanuel Makrlík ◽  
Petr Vaňura
Keyword(s):  
Molecular Weight ◽  
Polyethylene Glycol ◽  
Organic Phase ◽  
Perchloric Acid ◽  
Equilibrium Constants ◽  
Polyethylene Glycols ◽  
Individual Species ◽  
Nitrobenzene Solution ◽  
Separation Factors ◽  
Equilibrium Data

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.

Extraction of polyethylene glycols with dicarbolide solutions in nitrobenzene

1990 ◽  
Vol 55 (8) ◽  
pp. 1959-1967 ◽  
Author(s):  
Petr Vaňura ◽  
Pavel Selucký
Keyword(s):  
Polyethylene Glycol ◽  
Molecular Mass ◽  
Extraction Constant ◽  
Metal Extraction ◽  
Polyethylene Glycols ◽  
Relative Molecular Mass ◽  
Published Data ◽  
Average Molecular Mass ◽  
Peg 400 ◽  
Extraction Constants

The extraction of polyethylene glycol of average molecular mass 400 (PEG 400) with dicarbolide solution in nitrobenzene and of longer-chain polyethylene glycol, of average molecular mass 1 500 (PEG 1 500), with chlorinated dicarbolide solution in nitrobenzene was studied. During the extraction of PEG 400, the polyethylene glycol solvates the Horg+ ion in the organic phase giving rise to the HLorg+ species (L is polyethylene glycol). The obtained value of the extraction constant Kex(HLorg+) = 933 is consistent with published data of metal extraction. Extraction of PEG 1 500 was treated applying the simplified assumption that the thermodynamic behaviour of PEG 1 500 is the same as that of n molecules of polyethylene glycol with relative molecular mass 1 500/n, each solvating one cation. For this model, the value of n = 3.2 ± 1.1 and the values of the extraction constants of the HL1/n,org+ and HL2/n,org+ species were obtained by using the adapted program LETAGROP. This value of n is consistent with published extraction data in the presence of polyethylene glycol with a relative molecular mass from 200 to 1 000.

Extraction of europium from acidic aqueous solutions into nitrobenzene by dicarbolide in the presence of polyethylene glycol

1984 ◽  
Vol 49 (6) ◽  
pp. 1367-1381 ◽  
Author(s):  
Petr Vaňura ◽  
Marie Benešová ◽  
Emanuel Makrlík ◽  
Miroslav Kyrš ◽  
Jiří Rais
Keyword(s):  
Polyethylene Glycol ◽  
Aqueous Solutions ◽  
Organic Phase ◽  
Perchloric Acid ◽  
Distribution Ratio ◽  
Europium Complexes ◽  
Peg 400 ◽  
Extraction Constants ◽  
Positively Charged ◽  
The Eu

Extraction of microamounts of 152, 154 Eu from the aqueous solutions of perchloric acid (c(HClO4) = 0.1-0.5 mol l-1) was studied in the presence of 3 . 10-4 -0.3 mol l-1 of polyethylene glycol PEG 400 (L) by the nitrobenzene solutions of Co(III)-dicarbolide (3.3'-commo-bis(undecahydro-1,2-dicarba-3-cobalta-closo-dodecarborate) (-1), {(π-(3)-1,2-B9C2H11)2Co}-, henceforth only B-) of the concentration c(dicarbolide) = 10-3-10-1 mol l-1. Maxima of the Eu distribution ratio dependence on the concentration of polyethylene glycol are explained by the competition reactions between the positively charged europium complexes (EuL3+, EuLH-12+, and EuL23+, EuL2H-22+, or EuL33+) and protonized polyethylene glycol (HL+) in the organic phase. The respective equilibrium extraction constants were determined.

Extraction of strontium with dicarbolide in the presence of polyethylene glycol

1979 ◽  
Vol 44 (1) ◽  
pp. 157-166 ◽  
Author(s):  
Petr Vaňura ◽  
Jiří Rais ◽  
Pavel Selucký ◽  
Miroslav Kyrš
Keyword(s):  
Experimental Data ◽  
Polyethylene Glycol ◽  
Ionic Strength ◽  
Aqueous Phase ◽  
Organic Phase ◽  
Distribution Ratio ◽  
Equilibrium Constants ◽  
Electrostatic Charge ◽  
Peg 400 ◽  
Order Of Magnitude

The extraction of microquantities of 85Sr in the presence of 3 . 10-4 - 0.25 mol l-1 polyethylene glycol (PEG 400) (L) with solutions of dicarbolide ({(π-(3)-1,2-B9C2H11)2Co}-) in nitrobenzene (10-3 - 10-2M) was investigated. The occurrence of the maxima (up to one order of magnitude) on the plots of the strontium distribution ratio vs the total PEG concentration was explained in terms of the competition between the charged strontium-PEG complex (SrL2+) and protonized PEG (HL+) during the balancing of the dicarbolide electrostatic charge in the organic phase. Theoretical relations were derived for the shape of this dependence, for the effect of the acid concentration in the aqueous phase and that of the dicarbolide concentration in the organic phase, as well as for the positions of the corresponding maxima. The theoretical dependences are in accordance with the experimental data. The values of the concentration equilibrium constants of the reactions Sr2+ + L + 2 H+ ##e SrL2+ + 2 H+ (Kex(SrL2+)) and H+ + L ##e HL+ (Kex(HL+)) (for variable ionic strength) are Kex(SrL2+) = 3.26 . 108 and Kex(HL+) = 538 at 25 °C.

Extraction of strontium and barium salts by the nitrobenzene solution of dicarbolide in the presence of glymes

1985 ◽  
Vol 50 (3) ◽  
pp. 581-599 ◽  
Author(s):  
Petr Vaňura ◽  
Emanuel Makrlík
Keyword(s):  
Stability Constants ◽  
Organic Phase ◽  
Equilibrium Constants ◽  
Minor Role ◽  
Nitrobenzene Solution ◽  
Ligand Structure ◽  
Stability Constants Of Complexes ◽  
Separation Factors ◽  
The Stability ◽  
A Minor

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.

Hydration of Complexes of Some Univalent Cations with Polyethylene Glycol Ligands in Nitrobenzene Saturated with Water

1992 ◽  
Vol 57 (2) ◽  
pp. 289-295 ◽  
Author(s):  
Emanuel Makrlík
Keyword(s):  
Polyethylene Glycol ◽  
Hydration Numbers ◽  
Univalent Cations ◽  
Peg 400

The hydration numbers of the complexes ML+ formed by some univalent cations (M+ = Li+, Na+, NH4+, K+, Rb+ and Cs+) and polyethylene glycol ligands (L = PEG 200, PEG 300 and PEG 400) in nitrobenzene saturated with water were determined. The highest differences between the hydration numbers of the cations M+ and the complexes ML+ were found in the systems with the Na+ cation.

scholarly journals Liquid-Liquid Extraction of Transition Metal Cations by Glyoximes and Their Macrocyclic Glyoxime Ether Derivatives

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Nazan Karapinar ◽  
Emin Karapinar ◽  
Emine Ozcan
Keyword(s):  
Transition Metal ◽  
Transition Metals ◽  
Crown Ether ◽  
Aqueous Phase ◽  
Organic Phase ◽  
Equilibrium Constants ◽  
Liquid Extraction ◽  
Extraction Equilibrium ◽  
Liquid Liquid Extraction ◽  
Extraction Constants

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.

Calix[4]arene-crown-5 as a selective extraction reagents for K+/H+, Rb+/H+ and Rb+/Cs+ separations

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Petr Vaňura ◽  
Emanuel Makrlík ◽  
Pavel Selucký
Keyword(s):  
Stability Constants ◽  
Aqueous Phase ◽  
Organic Phase ◽  
Selective Extraction ◽  
Nitrobenzene Solution ◽  
Two Phase ◽  
Extraction Constants ◽  
Exchange Extraction ◽  
Phase Water ◽  
The Stability

Abstract From extraction experiments, the exchange extraction constants corresponding to the general equilibriums M+ (aq) + NaL+ (org) ⇔ ML+ (org) + Na+ (aq) or M+ (aq) + CsL+ (org) ⇔ ML+ (org) + Cs+ (aq), which take place in the two-phase water–nitrobenzene extraction system (M+ = Li+, H3O+, Ag+, K+, NH4 +, Tl+, Rb+; L = calix[4]arene-bis crown5(1,3-alternate), 26,28-dipropoxycalix[4]arene-crown-5(1,3-alternate), 11,23-dibromo-25,28-dipropoxycalix[4]arene-crown-5 (1,3-alternate) and 1,3-alternate-25,27-dihydroxycalix[4]arene-crown-5; aq = aqueous phase, org = organic phase), were evaluated. The stability constants of the NaL+ and CsL+ complexes were calculated from the extraction of the respective picrates in the system of water–nitrobenzene solution of L. Further, the stability constants of the ML+ complexes in nitrobenzene saturated with water were determined. High selectivities were found in some systems under study.

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