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 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.

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.

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.

The Extraction of Strontium and Barium with a Solution of Bis-1,2-Dicarbollylcobaltate in Nitrobenzene in the Presence of 18-Crown-6

1993 ◽  
Vol 58 (6) ◽  
pp. 1324-1336 ◽  
Author(s):  
Petr Vaňura ◽  
Emanuel Makrlík
Keyword(s):  
Aqueous Solution ◽  
Stability Constants ◽  
Organic Phase ◽  
Perchloric Acid ◽  
Extraction Constants ◽  
Individual Extraction Constants

A study has been made of the extraction of Sr and Ba in an aqueous solution of perchloric acid-18-crown-6-bis-1,2-dicarbollylcobaltate-nitrobenzene. It was found that the organic phase contains complexes of the ML2+org type ( M = Sr2+, Ba2+) that are converted to ML22+org when the concentration of crown (cL) is greater than the concentration of bis-1,2-dicarbollylcobaltate (cB). The values of the corresponding extraction constants, individual extraction constants and stability constants of the extracted species in the organic phase were determined. The system can be utilized for separation applications at concentrations here cL < cB.

Extraction of scandium, cerium, promethium, and europium with dibutylphosphoric, bis(2-ethylhexyl)phosphoric, and dioctylphosphoric acids in Freon 113

1987 ◽  
Vol 52 (2) ◽  
pp. 322-328 ◽  
Author(s):  
Petr Linhart ◽  
Oldřich Navrátil ◽  
Josef Havel ◽  
Milan Vrchlabský
Keyword(s):  
Aqueous Solutions ◽  
Aqueous Phase ◽  
Acid Concentration ◽  
Organic Phase ◽  
Hydrogen Ions ◽  
Inorganic Acid ◽  
Extraction Constants ◽  
Distribution Constants ◽  
Phosphoric Acids

The extraction of Sc, Ce, Pm, and Eu from aqueous solutions of HClO4 and HNO3 into organic phases constituted by solutions of dialkylphosphoric acids in Freon 113 was studied. The effects of the kind of inorganic acid, concentration of hydrogen ions in the aqueous phase and concentration of the extracting agent in the organic phase were examined. Based on the dependences of the distribution ratios of the metals on the above variables, the compositions of the extractable complexes were determined and the extraction constants calculated. The dimerization constants and distribution constants of the monomer were also determined for dibutylphosphoric and bis(2-ethylhexyl)phosphoric acids.

Extraction of some metals into solutions of 1-phenyl-3-methyl-4-benzoylpyrazolone-5 in freon 113

1980 ◽  
Vol 45 (4) ◽  
pp. 1221-1226 ◽  
Author(s):  
Oldřich Navrátil ◽  
Pavel Linhart
Keyword(s):  
Ionic Strength ◽  
Aqueous Solutions ◽  
Stability Constants ◽  
Aqueous Phase ◽  
Organic Phase ◽  
Extraction Constants ◽  
Distribution Constants ◽  
The Stability

The partition of 1-phenyl-3-methyl-4-benzoylpyrazolone-5 (HA) between aqueous solutions of HClO4 and NaClO4, ionic strength 0.1, and Freon 113 or its 2 : 1 mixture with benzene was studied. The logarithms of the HA distribution constants are 2.84 ± 0.10 and 3.39 ± 0.15 for the two organic phases, respectively. The extraction curves of cerium(III) and europium(III) revealed that in dependence on the pH of the aqueous phase, the metals are transferred into the organic phase in the form of the MA3 complexes (M = Ce, Eu). The stability constants of the complexes MAn in the aqueous phase were determined along with their distribution and extraction constants. For cobalt, zinc, and hafnium, a part of the extraction curves could only be studied, only the extraction constants were therefore determined. The sparing solubility of HA in Freon 113 can be circumvented by using a Freon-benzene mixture 2 : 1, which is still practically incombustible.

Distribution of dibenzyl sulfoxide between the aqueous and organic phases

1979 ◽  
Vol 44 (6) ◽  
pp. 1918-1924 ◽  
Author(s):  
František Vláčil ◽  
Huynh Dang Khanh
Keyword(s):  
Aqueous Solution ◽  
Nitric Acid ◽  
Perchloric Acid ◽  
Distribution Ratio ◽  
Protonation Constant ◽  
Metal Salts ◽  
Acid Solutions ◽  
Lower Solubility ◽  
Extraction Constants ◽  
Distribution Constants

The distribution of dibenzyl sulfoxide (DBSO) between toluene or tetrachloromethane and aqueous solution of nitric, hydrochloric, or perchloric acid was investigated for different acid concentrations. The solubility of DBSO in the two solvents was established (0.0555 mol l-1 in toluene, 0.0121 mol l-1 in tetrachloromethane at 20 °C) and its distribution constants KD were determined for the systems toluene-water and CCl4-water (133.7 and 27.4, respectively, at 20 °C). Employing the dependence of the distribution ratio of DBSO on the Hammett function for nitric and perchloric acids solutions (1-6M) and taking into account the extraction of the solvates of these acids as described previously, the value of the DBSO protonation constant was calculated to be KH1 (B + H+ ##e BH+) = 1.00 . 10-2, and more accurate values of the extraction constants of the nitric acid solvates were obtained, Kex1 (HNO3 . B) 1.1 . 10-3 and Kex2 ((HNO3)2 . B) 4.3 . 10-5. Owing to the lower solubility of DBSO in water as well as in acid solutions as compared with aliphatic or cyclic sulfoxides and also with tri-n-butylphosphate, solution of DBSO in toluene suits better as the stationary phase for extraction chromatography of metal salts.

A Simple Approach to the One-Pot Three Component Synthesis of 4Hpyrimido [2,1-b] benzothiazole Derivatives Using Polyethylene Glycol (PEG-400)

2015 ◽  
Vol 12 (3) ◽  
pp. 197-204 ◽  
Author(s):  
Prabhakar Rairala ◽  
Bandi Yadagiri ◽  
Rajashaker Bantu ◽  
Vijayacharan Guguloth ◽  
Lingaiah Nagarapu
Keyword(s):  
Polyethylene Glycol ◽  
Simple Approach ◽  
One Pot ◽  
Benzothiazole Derivatives ◽  
Peg 400 ◽  
The One

Extraction of hafnium(IV) with organophosphorus reagents from solutions of mineral acids mixtures

1979 ◽  
Vol 44 (12) ◽  
pp. 3656-3664
Author(s):  
Oldřich Navrátil ◽  
Jiří Smola ◽  
Rostislav Kolouch
Keyword(s):  
Ionic Strength ◽  
Aqueous Phase ◽  
Organic Phase ◽  
Perchloric Acid ◽  
Synergic Effect ◽  
Salting Out ◽  
Initial Concentration ◽  
Mixed Complexes ◽  
Synergic Extraction ◽  
Mineral Acids

Extraction of hafnium(IV) was studied from solutions of mixtures of perchloric and nitric acids and of perchloric and hydrochloric acids for constant ionic strength, I = 2, 4, 6, or 8, and for cHf 4 . 10-4 mol l-1. The organic phase was constituted by solutions of some acidic or neutral organophosphorus reagents or of 2-thenoyltrifluoroacetone, 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone, or N-benzoyl-N-phenylhydroxylamine in benzene, chloroform, or n-octane. A pronounced synergic extraction of hafnium proceeds only on applying organophosphorus reagents from an aqueous phase whose acidity is not lower than 3M-(HClO4 + HNO3) or 5M-(HClO4 + HCl). The synergic effect was not affected markedly by a variation of the initial concentration of hafnium in the range 1 . 10-8 -4 .10-4 mol l-1, it lowered with increasing initial concentration of the organophosphorus reagent and decreasing concentration of the H+ ions. It is suggested that the hafnium passes into the organic phase in the form of mixed complexes, the salting-out effect of perchloric acid playing an appreciable part.

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