Extraction of iron(III) from the citric medium by the toluene solution of trilaurylamine

1980 ◽  
Vol 45 (11) ◽  
pp. 3116-3129 ◽  
Author(s):  
Petr Vaňura ◽  
Libor Kuča
Keyword(s):  
Citric Acid ◽  
Ionic Strength ◽  
Aqueous Phase ◽  
Organic Phase ◽  
Toluene Solution ◽  
Constant Ionic Strength ◽  
Extraction Constants ◽  
Equilibrium Concentrations

The composition of Fe(III) complexes extracted from the aqueous phase of constant ionic strength (1M-(H3,Na3,Fe)A, where H3A denotes citric acid) by the toluene solution of trilaurylamine (TLA) has been determined and the respective extraction constants have been calculated. In the concentration range cFe < 10-2 mol l-1 FeA(TLA)2 and FeA(TLA)4(H3A)2-4 are the predominant complexes in the organic phase. The abundance of the (FeA)3(TLA)6(H3A)2 complex in the organic phase increases at higher equilibrium concentrations of Fe(III) in the aqueous phase and at higher concentrations of TLA.

Extraction of hexavalent uranium from citrate medium by the toluene solution of trilaurylamine

1983 ◽  
Vol 48 (1) ◽  
pp. 41-51
Author(s):  
Petr Vaňura ◽  
Libor Kuča
Keyword(s):  
Citric Acid ◽  
Aqueous Phase ◽  
Organic Phase ◽  
Equilibrium Concentration ◽  
Toluene Solution ◽  
Hexavalent Uranium

Complexes of the type (UO2HA)p(TLA)q(H3A)r are formed in the extraction of uranyl by the toluene solutions of trilaurylamine (TLA) from the isomolar aqueous phase formed by 1M-(H, Na,(UO2)0.5)3A, where H3A is citric acid. The extraction was studied at pH 1.62 with the equilibrium concentration of uranium in the aqueous phase in the range 10-4 -10-1 mol l-1 and with TLA concentration in the organic phase ranging from 0.0305 to 0.308 mol l-1. Complexes with q=5 and p+r=3 predominate in the extraction by TLA solutions of lower concentrations (c(TLA) = 0.0305 mol l-1). The fraction of more associated complexes (q=8-9, q - (p+r=0-2) increase with the increase of TLA concentration.

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.

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.

Extraction of hafnium by means of some substituted 1-phenyl-3-methyl-4-benzoyl-pyrazol-5-ones

1981 ◽  
Vol 46 (8) ◽  
pp. 1901-1905 ◽  
Author(s):  
Oldřich Navrátil ◽  
Jiří Smola
Keyword(s):  
Ionic Strength ◽  
Aqueous Phase ◽  
Dissociation Constants ◽  
Parent Substance ◽  
Benzoyl Group ◽  
Extraction Constants ◽  
Extraction Parameters ◽  
Substituted 1

Distribution between aqueous phase and benzene or chloroform was studied for 1-phenyl-3-methyl-4-benzoylpyrazol-5-ones with 2-chloro, 4-methoxy, 3-nitro, and 4-nitro substitution in the benzoyl group (ionic strength of the aqueous phase 0.1) and for hafnium in their presence (ionic strength 2.0). The distribution and dissociation constants of the reagents and the extraction constants of their hafnium complexes were determined. Hafnium was found to be extracted as the HfA4 species. The extraction parameters of the derivatives in question do not differ substantially from those of the parent substance.

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 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.

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.

Effets des cations alcalins et pseudo-alcalins sur quelques équilibres et en particulier sur l'équilibre d'extraction de l'acide thiocyanique par la méthylisobutylcétone

1976 ◽  
Vol 54 (1) ◽  
pp. 19-23
Author(s):  
Louise Schriver
Keyword(s):  
Ionic Strength ◽  
Equilibrium Constant ◽  
Aqueous Phase ◽  
Association Constant ◽  
Ion Pairs ◽  
Constant Ionic Strength ◽  
Thiocyanic Acid ◽  
Alkaline Cations ◽  
Methylisobutyl Ketone

The equilibrium constant for the extraction of thiocyanic acid by methylisobutyl ketone at constant ionic strength, depends on the nature of alkaline cations present in the aqueous phase. The phenomenon could be explained by the existence of ion pairs for which the association constant Kp is derivable. However the extraction of chlorpromazinium thiocyanate by the same solvent and the formation of the monothiocyanate complex of zirconium in aqueous phase are both independent of the nature of the electrolyte. The observed variations for the extraction of thiocyanic acid which exist also for the extraction of hydrochloric and perchloric acids by methylisobutyl ketone, result from the variation of species activities with a change in the identity of the cations.

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.

Atropine and quinine ionic associates with some acid dyes

1988 ◽  
Vol 53 (8) ◽  
pp. 1655-1663 ◽  
Author(s):  
Jan Souček ◽  
Emil Halámek ◽  
Roman Kysilka
Keyword(s):  
Ionic Strength ◽  
Aqueous Solutions ◽  
Aqueous Phase ◽  
Bromothymol Blue ◽  
Acid Dyes ◽  
Extraction Recovery ◽  
Extraction Constants ◽  
Ionic Associates ◽  
Metanil Yellow ◽  
Extraction Spectrophotometry

The formation of ionic associates of atropine and quinine with bromothymol blue, metanil yellow and cresol red was studied by extraction spectrophotometry. In aqueous solutions, formation of ionic associates was only observed for quinine with bromothymol blue; ionic associates of both dyes with all of the three dyes could be, however, studied by their extraction into chloroform. The conditional extraction constants were calculated for the equilibria involved. The ability of atropine, quinine and bromothymol blue to be extracted into chloroform was examined in dependence on pH and ionic strength of the aqueous phase. The pH1/2 value corresponding to 50% extraction recovery decreases with increasing ionic strength for quinine whereas for atropine the extraction recovery is only slightly affected by a higher ionic strength and for bromothymol blue the pH1/2 (E = 50%) value increases with increasing ionic strength.

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