Solvent Extraction of Mono(salicylato)beryllium, and the pH Titration of the System Beryllium-Salicylic Acid

1962 ◽  
Vol 15 (2) ◽  
pp. 218 ◽  
Author(s):  
Bruin HJ de ◽  
D Kairaitis ◽  
L Szego
Keyword(s):  
Salicylic Acid ◽  
Ionic Strength ◽  
Solvent Extraction ◽  
Aqueous Solutions ◽  
Distribution Ratio ◽  
Free Ligand ◽  
Ph Titration ◽  
Maximum Value ◽  
The Stability ◽  
Beryllium Complexes

It has been shown that a salicylatoberyllium complex can be extracted from aqueous solutions by aliphatic alcohols. The distribution ratio is a symmetrical function of the logarithm of the free ligand concentration and passes through a maximum value ; the stability constants of the mono- and bis(salicylato)beryllium complexes have been determined from the data for points of equal extraction. The values obtained in this way are β1 = 4.1 x 1012 and β2 = 4.3 x 1022, in an ionic strength of 0.15. They agree fairly well with those obtained by pH-titration procedures, which are β1 = 6.1 x 1012 and β2 =7 x 1022.

The Extraction of Anionic Beryllium Complexes by Tri-iso-octylamine

1962 ◽  
Vol 15 (3) ◽  
pp. 457 ◽  
Author(s):  
HJ de Bruin ◽  
D Kairaitis ◽  
RB Temple
Keyword(s):  
Aqueous Solution ◽  
Stability Constants ◽  
Complexing Agents ◽  
Conditional Stability ◽  
Tertiary Amines ◽  
Ph Titration ◽  
Anionic Complexes ◽  
The Stability ◽  
Conditional Stability Constants ◽  
Beryllium Complexes

The extraction of beryllium from aqueous solution by long-chain tertiary amines has been observed in the presence of ligands giving rise to anionic complexes. The nature of the oxalate complex extracted by solutions of tri-iso-octylamine in chloroform has been studied in detail and the species formed in the organic phase were shown to have the composition Be(C2O4)2.{NH(i-C8H15)3}2. The complexes formed in aqueous solution between beryllium and several anionic complexing agents have been examined by the method of pH-titration. Conditional stability constants have been obtained for the complexes formed with oxalic, malonic, maleic, succinic, phthalic, and salicylic acids. Differences in their extractabilities can be explained semiquantitatively with the help of the stability constants and the acid association constants of the complexing agents.

Europium tartronate and mandelate ion association in water

1967 ◽  
Vol 45 (14) ◽  
pp. 1643-1647 ◽  
Author(s):  
P. G. Manning
Keyword(s):  
Ionic Strength ◽  
Solvent Extraction ◽  
Stability Constant ◽  
Stability Constants ◽  
Ion Association ◽  
Tridentate Ligand ◽  
Radiotracer Method ◽  
The Stability ◽  
Two Stages ◽  
Low Ionic Strength

Stepwise stability constants have been determined for the 1:1 and 1:2 Eu3+:mandelate− and Eu3+:tartronate2− complexes in water. Measurements were made at low ionic strength and the temperature was 25 °C. The solvent-extraction–radiotracer method was used.For the mandelate system at an ionic strength of 0.104, K1 = 5.0 × 102, K2 = 1.58 × 102, and K1:K2 = 3.1. The K1:K2 ratios suggest monodentate ligandcy.The stepwise stability constants for the two stages of tartronate ion association are: K1 = 7.1 ( ± 15%) × 104 and K1K2 = 4.2 ( ± 5%) × 108. The magnitudes of the stability constants suggest that tartronate is a tridentate ligand. The stability constant ratios are discussed with reference to the ratios for piperidinedicarboxylate and iminodiacetate complexes.

Thermodynamic modeling of metal-ligand interactions in high ionic strength NaCl solutions: the Co2+-oxalate system

2000 ◽  
Vol 88 (9-11) ◽  
Author(s):  
M. Borkowski ◽  
Gregory R. Choppin ◽  
Robert C. Moore
Keyword(s):  
Ionic Strength ◽  
Solvent Extraction ◽  
Stability Constant ◽  
Aqueous Solutions ◽  
High Ionic Strength ◽  
Pitzer Equations ◽  
Ligand Interactions ◽  
Oxalate Ion ◽  
Apparent Stability ◽  
Metal Ligand

First and second apparent stability constants for cobalt(II) with oxalate ion have been determined using solvent extraction. Data were collected in 0.3 m to 5.0 m NaCl aqueous solutions. The logarithms of first stability constant ranged from 3.30 ± 0.03 to 3.57 ± 0.03 and second stability constant ranged from 5.49 ± 0.05 to 6.02 ± 0.06. The data were modeled using the Pitzer equations. For the 1:1 complex, values of the μ

scholarly journals Effects of pH and Ionic Strength on the Stability of Nanobubbles in Aqueous Solutions of α-Cyclodextrin

2007 ◽  
Vol 111 (40) ◽  
pp. 11745-11749 ◽  
Author(s):  
Fan Jin ◽  
Junfang Li ◽  
Xiaodong Ye ◽  
Chi Wu
Keyword(s):  
Ionic Strength ◽  
Aqueous Solutions ◽  
Effects Of Ph ◽  
The Stability

scholarly journals 2,6-Bis((benzoyl-R)amino)pyridine (R = H, 4-Me, and 4-NMe2) Derivatives for the Removal of Cu(II), Ni(II), Co(II), and Zn(II) Ions from Aqueous Solutions in Classic Solvent Extraction and a Membrane Extraction

Membranes ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 233
Author(s):  
Daria Bożejewicz ◽  
Borys Ośmiałowski ◽  
Małgorzata Anna Kaczorowska ◽  
Katarzyna Witt
Keyword(s):  
Mass Spectrometry ◽  
Solvent Extraction ◽  
Aqueous Solutions ◽  
Metal Ions ◽  
High Resolution Mass Spectrometry ◽  
Membrane Extraction ◽  
Resonance Spectroscopy ◽  
Recovery Processes ◽  
The Stability ◽  
Derivatives Of

In this paper, the application of new substituted 2,6-bis((benzoyl-R)amino)pyridine (R = H, 4-Me, and 4-NMe2) derivatives for the recovery of copper(II), nickel(II), cobalt(II), and zinc(II) ions from aqueous solutions was described. The structures of the synthesized compounds were confirmed by nuclear magnetic resonance spectroscopy (NMR), electrospray ionization high-resolution mass spectrometry (ESI HRMS), and tandem mass spectrometry methods (HCD MS/MS). Three different derivatives of 2,6-bis((benzoyl-R)amino)pyridine were used as carriers in membrane processes and as extractants in classic solvent extraction. In each case, the single derivative recovery was carried out on a model solution that contained only one type of metal ions. Spectrophotometry studies were performed to determine the stability constants of the complexes formed by the synthesized species with analyzed metals ions. The results obtained indicate that the synthesized compounds form stable complexes with Cu(II), Ni(II), Co(II), and Zn(II) ions and can be used in both types of studied recovery processes. However, the effectiveness of the synthesized compounds in the recovery of metal ions depends both on the structure of compounds and properties of metals as well as on their concentration.

scholarly journals Thermodynamics of binary and ternary complexes of 3-amino-1, 2, 4-triazole and aminoacids with Ni(II) and Co(II) metal ions

2005 ◽  
Vol 70 (8-9) ◽  
pp. 1057-1066 ◽  
Author(s):  
Ayse Erçag ◽  
Tuba Sismanoglu ◽  
Suheyla Pura
Keyword(s):  
Ionic Strength ◽  
Aqueous Solutions ◽  
Glutamic Acid ◽  
Driving Force ◽  
Ternary Complex ◽  
Ternary Complexes ◽  
Binary And Ternary Complexes ◽  
Enthalpy Changes ◽  
Binary Complexes ◽  
The Stability

The stability constants of the 1:1 binary complexes of Ni(II) and Co(II) with 3-amino-1,2,4-triazole (AT), leucine (Leu) and glutamic acid (Glu), and the 1:1:1 ternary complex of them and the protonation constants of the ligands were determined potentiometrically at a constant ionic strength of I = 0.10 mol L-1 (NaClO4) in aqueous solutions at 15.0 and 25.0 ?C. The thermodynamic parameters ?Gf0, ?Hf0 and ?Sf0 are reported for the formation reactions of the complexes. The enthalpy changes of all the complexations were found to be negative but the entropy changes positive. While the driving force for the formation of the Ni(II), Co(II) ? AT complexes is the enthalpy decrease, the driving force for the ternary complexes of AT is the entropy increase.

THE STABILITY OF THIOCOMPLEXES AND SOLUBILITY PRODUCTS OF METAL SULPHIDES: I. CADMIUM SULPHIDE

1964 ◽  
Vol 42 (3) ◽  
pp. 662-668 ◽  
Author(s):  
J. Ste-Marie ◽  
A. E. Torma ◽  
A. O. Gübeli
Keyword(s):  
Ionic Strength ◽  
Aqueous Solutions ◽  
Total Concentration ◽  
Cadmium Sulphide ◽  
Radioactive Tracer ◽  
Tracer Technique ◽  
Radioactive Tracer Technique ◽  
Ph Values ◽  
Solubility Products ◽  
The Stability

The nature and stability of cadmium sulphide complexes in aqueous solutions have been investigated. The total concentration of the metal in solution was determined at constant temperature and ionic strength, and at various pH values, by a radioactive tracer technique.

scholarly journals Activity corrections for ionic equilibria in aqueous solutions

1980 ◽  
Vol 58 (12) ◽  
pp. 1253-1257 ◽  
Author(s):  
Mian S. Sun ◽  
Donald K. Harriss ◽  
Vincent R. Magnuson
Keyword(s):  
Ionic Strength ◽  
Stability Constant ◽  
Aqueous Solutions ◽  
General Formula ◽  
Stability Constants ◽  
Ionic Equilibria ◽  
Ion Activity ◽  
The Difference ◽  
Single Ion Activity ◽  
The Stability

Activity corrections for ionic equilibria in aqueous solutions at 25 °C and ionic strengths up to 0.5 have been investigated. An empirical formula for activity corrections was generated by statistically fitting stability constant data for approximately 540 complexes, for which both thermodynamic and concentration stability constants were known, to a modified Debye – Hückel relationship. The general formula is[Formula: see text]χ > 0, where Δ log K is the difference in the logarithms of the stability constants at infinite dilution and finite I (I ≤ 0.5), and χ is an even integer dependent only on the stoichiometry and charge of the ions involved. Activity correction formulae for ionic equilibria involving classes of ligands (amino acid, inorganic, amine, and organic acid) also were developed. The general formula predicts stability constant corrections within 0.1 log unit for 87 % of the data used at ionic strength 0.1 and 64 % of the data at ionic strength 0.5. In addition, single ion activity coefficients as a function of ionic strength, 0 < I ≤ 0.5, are presented.

Viscometric Studies on the Stability of DNA-Proflavine Complex-II

1974 ◽  
Vol 29 (3-4) ◽  
pp. 133-135 ◽  
Author(s):  
G. C. Das ◽  
N. N. Das
Keyword(s):  
Ionic Strength ◽  
Melting Temperature ◽  
Thermal Denaturation ◽  
Sodium Ion ◽  
Ion Concentration ◽  
Complex Ii ◽  
Maximum Value ◽  
Dye Binding ◽  
Stabilization Effect ◽  
The Stability

Abstract The binding of proflavine to native DNA increased its stability against thermal denaturation as measured by viscometric method. Up to a moderate ionic strength of 0.058 ᴍ, the melting temperature of the complex increased almost linearly with the increase of dye concentrations and a saturation was reached when one proflavine molecule was added per four to five DNA-Phosphates (D/P≅0.2). The extent of stabilization (ΔTm) produced by dye binding decreased gradually with the increase of ionic strength and no stabilization effect was observed at an ionic strength of about 0.3 ᴍ. The maximum melting temperature attained by Proflavine binding was almost independent of the ionic strength of the medium. The same maximum value was reached as obtained simply by increasing the sodium ion concentration.

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