scholarly journals Pb(II) Extraction with Benzo-18-Crown-6 Ether into Benzene under the Co-Presence of Cd(II) Nitrate in Water

Inorganics ◽  
2018 ◽  
Vol 6 (3) ◽  
pp. 77 ◽  
Author(s):  
Yoshihiro Kudo ◽  
Tsubasa Nakamori ◽  
Chiya Numako
Keyword(s):  
Ionic Strength ◽  
Conditional Distribution ◽  
Equilibrium Constants ◽  
Water Phase ◽  
Equilibrium Potential ◽  
Extraction Constants ◽  
Distribution Constants

Extraction of Pb(II) with picrate ion [Pic−] and 0, 0.58, 15, 48, or 97 mmol dm−3 Cd(NO3)2 by benzo-18-crown-6 ether (B18C6; L as its symbol) into benzene (Bz) was studied. Three kinds of extraction constants, Kex, Kex±, and KPb/PbL (or Kex2±), were determined at 298 K: these constants were defined as [PbLPic2]Bz/P, [PbLPic+]Bz[Pic−]Bz/P, and [PbL2+]Bz/[Pb2+][L]Bz (or [PbL2+]Bz([Pic−]Bz)2/P), respectively. The symbol P shows [Pb2+][L]Bz[Pic−]2 and the subscript “Bz” denotes the Bz phase, Bz saturated with water. Simultaneously, conditional distribution constants, KD,Pic (=[Pic−]Bz/[Pic−]), of Pic− with distribution equilibrium-potential differences (dep) were determined. Then, based on the above four constants and others, the component equilibrium constants of K1,Bz (=[PbLPic+]Bz/[PbL2+]Bz[Pic−]Bz), K2,Bz (=[PbLPic2]Bz/[PbLPic+]Bz[Pic−]Bz), and KD,PbL (=[PbL2+]Bz/[PbL2+]) were obtained. Using these constants, the Pb(II) extraction with B18C6 under the co-presence of Cd(II) in the water phase was characterized. In such a characterization, I and IBz dependences on the constants were mainly discussed, where their symbols denote the ionic strength of the water phase and that of the Bz one, respectively.

scholarly journals Determination of Distribution Equilibrium-Potential Differences Based on Extraction with Several Crown Ethers by Nitrobenzene, 1,2-Dichloroethane and Dichloromethane

2017 ◽  
Vol 9 (4) ◽  
pp. 110 ◽  
Author(s):  
Yoshihiro Kudo ◽  
Tomohiro Amano ◽  
Satoshi Ikeda
Keyword(s):  
Complex Formation ◽  
Conditional Distribution ◽  
Equilibrium Constants ◽  
Formation Constants ◽  
Equilibrium Potential ◽  
Complex Formation Constants ◽  
Extraction Constants ◽  
Distribution Constants ◽  
Extraction Equilibria

Extraction constants (Kex± & Kex) were determined at 298 K for the extraction of sodium picrate (NaPic) by nitrobenzene (NB), 1,2-dichloroethane (DCE) and dichloromethane using 3m-crown-m ethers and their benzo-derivatives (m = 5, 6; abbreviated as L) together with the determination of conditional distribution constants (KD,Pic) of picrate ion, Pic-, into these diluents. The K1,org (= [NaLPic]org/[NaL+]org[Pic-]org) values at the organic (org) phases, such as NB & DCE, were calculated from the relation Kex/Kex± = K1,org. Distribution equilibrium-potential differences (Dfeq) at extraction equilibria were evaluated from the equation Dfeq = -0.05916´(log KD,Pic - constant) at 298 K. Correlations of the above equilibrium constants, particularly Kex±, with Dfeq were examined. Furthermore, the standard formal potentials for Na+ transfers across the interfaces were briefly evaluated from calculated Dfeq, [Na+] and [Pic-]org. The above extraction systems were characterized by K1,org and the complex formation constants of Na+ with L in the org phases.

scholarly journals Extraction of Sodium Picrate by 3m-Crown-mEthers and Their Monobenzo Derivatives (m= 5, 6) into Benzene: Estimation of Their Equilibrium-Potential Differences at the Less-Polar Diluent/Water Interface by an Extraction Method

2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Yoshihiro Kudo ◽  
Tsubasa Nakamori ◽  
Chiya Numako
Keyword(s):  
Extraction Method ◽  
Ion Pair ◽  
Equilibrium Potential ◽  
Straight Line ◽  
Extraction Constants ◽  
Distribution Constants ◽  
The Individual ◽  
Polar Diluent ◽  
O Phase ◽  
Complex Ion

Individual distribution constants (KD,A) of picrate ion (Pic−) and extraction constants (Kex±) of NaPic by some crown ethers (L) into benzene (Bz) at 25°C were calculated from data reported previously. These constants were defined asKD,Pic=Pic-o/[Pic-]andKex±=NaL+oPic-o/(Na+Lo[Pic-]), respectively. Here, the subscript “o” denotes an organic (o) phase and practically o = Bz. 15-Crown-5 ether (15C5), 18-crown-6 one (18C6), and their monobenzo (B) derivatives (B15C5 and B18C6) were selected as L. Interfacial equilibrium-potential differences (Δϕeq) at extraction were estimated at 298 K. A plot oflog⁡Kex±versus-Δϕeqfor the four L extraction systems gave a straight line with slope = 84 V−1. This slope was compared with those, reported before, of the dichloromethane (DCM), 1,2-dichloroethane (DCE), and nitrobenzene (NB) extraction systems. The slopes of the regression lines were in the order NB < DCM ≤ DCE < Bz. Also, the individual distribution constants of the complex ionNaL+and an ion-pair complex (NaL+Pic-) into Bz phase were calculated from the above extraction data. At least, a comparison between these values suggests that Bz molecules mainly interact withNaL+moiety ofNaL+Pic-.

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 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.

Examination of the Conditions of Extraction of Toxic Organic Bases and of Methods of Their Determination. III. Extraction of Ion-Associates of Dibenz[b,f]-1,4-oxazepin

1994 ◽  
Vol 59 (3) ◽  
pp. 582-588
Author(s):  
Jan Souček ◽  
Ladislav Belický ◽  
Josef Havel
Keyword(s):  
Aqueous Phase ◽  
Basic Dye ◽  
Organic Bases ◽  
Safranine T ◽  
Extraction Constants ◽  
Distribution Constants

The protonation and distribution constants of dibenz[b, f]-1,4-oxazepin (CR) were measured. This substance forms stable ion-associates with Acid Red 88, extractable into chloroform. Reextraction with an aqueous phase containing basic fuchsine or safranine T brings about exchange of the CR cation for the basic dye cation. The associates so formed exhibit higher conditional extraction constants and higher molar absorptivities than the initial associates.

Extraction of rare earth metals from trichloroacetate solutions in the presence of linear polyoxonium compounds

1991 ◽  
Vol 56 (8) ◽  
pp. 1585-1592 ◽  
Author(s):  
Petr Vaňura
Keyword(s):  
Rare Earth ◽  
Nonionic Surfactant ◽  
Separation Factor ◽  
Rare Earth Metals ◽  
Extraction Constants ◽  
Distribution Constants ◽  
Factor Α

Extraction of rare earth metals from lithium trichloroacetate solutions ( 1.20-2.88 mol l-1) with solutions of the commercial nonionic surfactant Slovafol 909 (p-nonylphenylnonaethylene glycol) in chloroform and dichloromethane was investigated. The extraction constants as well as the Slovafol 909 distribution constants were determined in the water-dichloromethane and water-chloroform systems. The lanthanide distribution ratios decrease with their atomic numbers first rather rapidly (approximately to Sm): the separation factor αSmLa = 1.54 and 1.87 in dichloromethane and in chloroform, respectively; for lanthanides with higher atomic numbers the drop is less pronounced (αLuLa = 2.42 and 2.85 in the two solvents, respectively).

Thermodynamics of chelation. II. Iron(II) and zinc(II) complexes of 6-Methylpyridine-2-aldehyde 2'-pyridylhydrazone

1969 ◽  
Vol 22 (11) ◽  
pp. 2333 ◽  
Author(s):  
RW Green ◽  
WG Goodwin
Keyword(s):  
Ionic Strength ◽  
Equilibrium Constants

6-Methylpyridine-2-aldehyde 2?-pyridylhydrazone is a stronger base but weaker ligand than its parent, paphy. Equilibrium constants are reported for seven temperatures from 5� to 60� and over a range of ionic strength. The properties of the ligand are discussed in terms of the derived enthalpies and entropies of reaction.

SOME EQUILIBRIUM CONSTANTS OF TRANSITION METAL HALIDES

1960 ◽  
Vol 38 (10) ◽  
pp. 1827-1836 ◽  
Author(s):  
M. W. Lister ◽  
P. Rosenblum
Keyword(s):  
Ionic Strength ◽  
Transition Metal ◽  
Equilibrium Constant ◽  
Spectrophotometric Method ◽  
Equilibrium Constants ◽  
Cell Voltage ◽  
Metal Halides ◽  
Complex Ions ◽  
Anomalous Variation ◽  
A Cell

Measurements are reported on the formation of complex ions in solutions containing cupric and chloride or bromide ions, and solutions of nickel or cobalt with chloride. In each case the halide was present in very low amount. With copper a spectrophotometric method was used, and a cell voltage method with nickel and cobalt. The ionic strength was kept constant, but the temperature was varied. The data show difficulties of interpretation if it is assumed that only MX+ ions (M is the metal, X is the halogen) are formed, the difficulties arising from the anomalous variation of the equilibrium constant with temperature, and from the general drift of the calculated constants from the e.m.f. measurements. Various explanations are considered and it is shown that postulation of M2X+3 ions is at least a possible explanation.

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