scholarly journals Comparative Extraction of Aluminum Group Metals Using Acetic Acid Derivatives with Three Different-Sized Frameworks for Coordination

Separations ◽  
2021 ◽  
Vol 8 (11) ◽  
pp. 211
Author(s):  
Keisuke Ohto ◽  
Nako Fuchiwaki ◽  
Hiroaki Furugou ◽  
Shintaro Morisada ◽  
Hidetaka Kawakita ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Metal Ions ◽  
Spectroscopic Data ◽  
Equilibrium Constants ◽  
Structural Effects ◽  
Extraction Equilibrium ◽  
Ph Values ◽  
Slope Analysis ◽  
Coordination Sites ◽  
Extraction Properties

We prepared acetic acid derivatives using three different frameworks, calix[4]arene, alkenyltrimethylol, and trihydroxytriphenylmethane, which differ in the number and size of their coordination sites. We further investigated the extraction properties for aluminum group metal ions. All three extraction reagents exhibited increased extraction compared with the corresponding monomeric compounds, owing to structural effects. The extraction reaction and extraction equilibrium constants were determined using a slope analysis. Their extraction abilities, separation efficiencies, and potential coordination modes are discussed using the extraction equilibrium constants, half-pH values, and spectroscopic data. The calix[4]arene and trihydroxytriphenylmethane derivatives demonstrated allosteric co-extraction of indium ions (In3+) with an unexpected stoichiometry of 1:2.

scholarly journals New Trident Molecule with Phosphoric Acid Functionality for Trivalent Rare Earth Extraction

2017 ◽  
Vol 17 (3) ◽  
pp. 491 ◽  
Author(s):  
Keisuke Ohto ◽  
Hiromasa Murashima ◽  
Hiroshi Murakami ◽  
Shintaro Morisada ◽  
Hidetaka Kawakita ◽  
...  
Keyword(s):  
Rare Earth ◽  
Phosphoric Acid ◽  
Rare Earths ◽  
Equilibrium Constants ◽  
Extraction Equilibrium ◽  
Ph Values ◽  
Extraction Behavior ◽  
Separation Factors ◽  
Trivalent Rare Earth ◽  
Rare Earth Extraction

Tripodal extraction reagent with three phosphoric acid groups, together with the corresponding monopodal molecule has been prepared to investigate some metals extraction behavior, in particular, trivalent rare earth elements (REEs). The tripodal reagent exhibited extremely high selectivity for metals with high valency such as Zr(IV), In(III), Lu(III), and Fe(III). Tripodal reagent also exhibited exceptionally high extraction ability compared with the corresponding monopodal one in the extraction of trivalent rare earths. The result for the stoichiometry of tripodal reagent to heavy rare earths showed the inflection point between Er (2:1 for a ligand with ion) and Tm (1:1). The extraction reactions were determined for all rare earths with both reagents. The extraction equilibrium constants (Kex), the separation factors (β), half pH values (pH1/2), difference half pH values (ΔpH1/2) for extraction of REEs with both reagents are estimated.

Synthesis of a Novel Dibenzylamide Derivative of p-tert-Octylcalix[4]arene and its Extraction Properties Towards Noble Metal Ions

2017 ◽  
Vol 70 (5) ◽  
pp. 450 ◽  
Author(s):  
Jee Young Kim ◽  
Yoga Priastomo ◽  
Shintaro Morisada ◽  
Hidetaka Kawakita ◽  
Keisuke Ohto ◽  
...  
Keyword(s):  
Nitric Acid ◽  
Solvent Extraction ◽  
Metal Ions ◽  
Contact Time ◽  
Nitric Acid Concentration ◽  
Precious Metals ◽  
Extractant Concentration ◽  
Acid Media ◽  
Slope Analysis ◽  
Extraction Properties

A N,N-dibenzylacetoamide derivative of p-tert-octylcalix[4]arene was synthesised and its solvent extraction of precious metals in nitric acid media was investigated for determining the effects of extractant concentration and contact time as well as nitric acid concentration in comparison with a N,N-diethylacetoamide derivative. The extraction properties with both derivatives exhibited a slight difference. The extraction reaction of divalent palladium with both derivatives is discussed by slope analysis. The stripping behaviour of the extractant loaded with silver and palladium is also described using various stripping solutions.

CARBON-13 ISOTOPE EFFECTS IN SYSTEMS CONTAINING CARBON DIOXIDE, BICARBONATE, CARBONATE, AND METAL IONS

1965 ◽  
Vol 43 (3) ◽  
pp. 582-595 ◽  
Author(s):  
H. G. Thode ◽  
M. Shima ◽  
C. E. Rees ◽  
K. V. Krishnamurty
Keyword(s):  
Carbon Dioxide ◽  
Metal Ions ◽  
Equilibrium Constant ◽  
Spectroscopic Data ◽  
Isotope Effects ◽  
Equilibrium Constants ◽  
Equilibrium Mixture ◽  
Theoretical Evaluation ◽  
Fractionation Process ◽  
Best Fit

The fractionation of 13C between CO2(g) and CO3−--HCO3−(aq) in solution has been studied in single stage experiments using carbonic anhydrase to catalyze the hydration of CO2. Added metal ions, pH of the equilibrium mixture, and temperature are found to play important roles in the overall fractionation process. Theoretical evaluation of the 13CO2(g)--12CO3−(aq) equilibrium constant (K2) has been made using the most recent spectroscopic data on the exchanging species. The variation of the equilibrium constant K2 with temperature has been calculated for each 25 deg interval from 0 to 975 °C with the help of the McMaster University IBM 7040 computer. It is shown that the overall 13C fractionation in the system may be treated as contributions due mainly to three exchange equilibria whereby 13CO2(g) independently exchanges with 12CO2(aq), H12CO3(aq),and 12CO3−(aq), the corresponding equilibrium constants being K0, K1, and K2 respectively. The best fit values for the equilibrium constants are K0 = 1.0009, K1 = 1.0077, and K2 ≥ 1.013, indicating the order K0 < K1 < K2.

scholarly journals EXTRACTION OF METAL IONS BY 4-BENZOYL- OR 4-(3-NYTROBENZOYL-1-HEXYL- 3-METHYL-2-PYRAZOLINE-5-ONES

2020 ◽  
Vol 63 (9) ◽  
pp. 63-69
Author(s):  
Andrey E. Lesnov ◽  
Larisa V. Pustovik ◽  
Irina A. Sarana
Keyword(s):  
Metal Ions ◽  
Ph Dependence ◽  
Metal Extraction ◽  
Trioctylphosphine Oxide ◽  
Neutral Reagent ◽  
Coordination Sites ◽  
Extraction Properties ◽  
Triisobutyl Phosphate ◽  
Degree Of Extraction ◽  
Acidic Region

The extraction properties of solutions of 4-benzoyl- and 4- (3-nitrobenzoyl) -1-hexyl-3-methyl-2-pyrazolin-5-ones in chloroform were studied. The pH dependence of the degree of extraction is S-shaped. Ions Cu2+, Pb2+, Zn2+, Ni2+, Co2+, Mn2+, Cd2+, Ca2+, Mg2+ are extracted in the form of complexes with the ratio M (II): reagent determined by the equilibrium shift method equals to 1: 2. A lower equilibrium pH than the initial value indicates a cation-exchange extraction mechanism. The introduction of an electronegative nitro group into the benzoyl fragment of the reagent led to a shift in the pH50 values of the extraction of metal ions in a more acidic region. The presence of a correlation between the values of the Klopman hardness parameters of the above metal cations and extraction pH50 values was shown. The influence of the nature of the solvent on the extraction of zinc ions was studied. The addition of polar isopentanol to the extractant shifts the pH of the metal extraction to a more acidic region. In order to increase the pH50 value of zinc extraction, the solvents are arranged in a row: 30% isopentanol in CHCl3 < benzene < xylene < toluene < chloroform < dichloroethane. The introduction of additional neutral electron-donating hydrophobic organic compounds into the extract: 1-hexyl-3-methyl-2-pyrazolin-5-one, triisobutyl phosphate, trioctylphosphine oxide significantly increases the values of the partition coefficients of zinc. The observed synergistic effect is explained by the formation of a coordinatively unsaturated intracomplex compound of zinc with aroylpyrazolone, in which the free coordination sites are filled with neutral reagent molecules. In this case, water is replaced and due to the increased hydrophobicity of the complex, an increase in extraction occurs. Confirmation of the formation of a coordination-unsaturated zinc complex is a close to unity value of the slope of the decimal logarithm of the metal distribution constant for pH.

Study on desorption of Mn, Fe, and Mg from TMP and evaluation of the complexing strength of different chelating agents using side reaction coefficients 10th EWLP, Stockholm, Sweden, August 25–28, 2008

Holzforschung ◽  
2009 ◽  
Vol 63 (6) ◽  
Author(s):  
Kim Granholm ◽  
Pingping Su ◽  
Leo Harju ◽  
Ari Ivaska
Keyword(s):  
Citric Acid ◽  
Metal Ions ◽  
Chelating Agents ◽  
Side Reaction ◽  
Sodium Dithionite ◽  
Thermomechanical Pulp ◽  
Peroxide Bleaching ◽  
Ph Values ◽  
Reducing Environment ◽  
Ph Range

Abstract Chelation of thermomechanical pulp (TMP) was studied in this work. The desorption of Mn, Fe, and Mg due to their impact on peroxide bleaching was investigated. The desorption experiments were performed with EDTA, citric acid, oxalic acid, and formic acid as chelating agents at different pH. Chelation experiments with EDTA were carried out at pH 3–11. Sodium dithionite was used as the reducing agent in studying chelation with EDTA in a reducing environment. Mn was very effectively desorbed with EDTA from TMP at pH <10 and the reducing environment further improved the removal of all the studied metal ions from TMP with EDTA. Citric acid also removed Mn effectively from TMP at pH 5. The thermodynamic stability constants of different metal chelates do not present the correct picture of how strongly the metal ions are bound by the chelating agents in different conditions. But by means of the side reaction coefficients (α M(L)-coefficients) it is also theoretically possible to evaluate and compare the real binding strengths between the metal ions and different chelating agents at varying pH values and other solution conditions. In this study, a theory is given for the calculation of side reaction coefficients. Values of the α M(L)-coefficients, for the pH range 0–14, are presented for EDTA, DTPA, and also for some other new potential environmentally friendly chelating agents.

Bacterial Spoilage of Citrus Products at pH Lower than 3.51

1976 ◽  
Vol 39 (12) ◽  
pp. 819-822 ◽  
Author(s):  
B. J. JUVEN
Keyword(s):  
Acetic Acid ◽  
Lactic Acid ◽  
Thermal Resistance ◽  
Tartaric Acid ◽  
Lactobacillus Brevis ◽  
Acid Inhibition ◽  
Temperature Range ◽  
Ph Values ◽  
Sugar Syrup ◽  
Z Value

A strain of Lactobacillus brevis, L-3, was isolated from a blown can of grapefruit segments in sugar syrup; it caused spoilage of citrus products having pH values lower than 3.5. When inoculated into orange (pH 3.38) and grapefruit (pH 2.99) juices, after 5 h at 30 C L-3 produced 15 and 22 μg diacetyl/ml, respectively, and off-flavor was detectable. L-3 grew in APT broth acidified to pH 3.0 with citric, hydrochloric, phosphoric, or tartaric acid. However, its growth was inhibited at pH 3.6 if the acidulant was lactic acid, while with acetic acid inhibition occurred at a pH between 3.7 and 4.0. The thermal resistance of L-3 in orange serum (pH 3.4) was studied in the temperature range of 52 to 60 C: a z value of 8.3 was obtained. A simple and reliable capillary technique for studying the thermal resistance of gas-producing organisms in liquid foods and media is presented.

Effect of pH, Acidulant, Time, and Temperature on the Growth and Survival of Listeria monocytogenes

1989 ◽  
Vol 52 (8) ◽  
pp. 571-573 ◽  
Author(s):  
KENT M. SORRELLS ◽  
DAVIN C. ENIGL ◽  
JOHN R. HATFIELD
Keyword(s):  
Antimicrobial Activity ◽  
Acetic Acid ◽  
Lactic Acid ◽  
Listeria Monocytogenes ◽  
Citric Acid ◽  
Hydrochloric Acid ◽  
Malic Acid ◽  
Incubation Temperature ◽  
Growth And Survival ◽  
Ph Values

The effect of different acids, pH, incubation time, and incubation temperature on the growth and survival of four strains of Listeria monocytogenes in tryptic soy broth was compared. Hydrochloric acid (HCl), acetic acid (AA), lactic acid (LA), malic acid (MA), and citric acid (CA) were used to acidify tryptic soy broth to pH values 4.4, 4.6, 4.8, 5.0, and 5.2 pH. Incubation times were 1, 3, 7, 14, and 28 d at 10, 25, and 35°C. The inhibition of L. monocytogenes in the presence of high acidity appears to be a function of acid and incubation temperature. Based on equal pH values, the antimicrobial activity is AA &gt; LA &gt; CA ≥ MA &gt; HCl at all incubation times and temperatures. When based on equal molar concentration, the activity appeared to be CA ≥ MA &gt; LA ≥ AA &gt; HCl at 35 and 25°C, and MA &gt; CA &gt; AA ≥ LA &gt; HCl at 10°C. Greatest antimicrobial activity occurred at 35°C. Greatest survival occurred at 10°C and greatest growth occurred at 25°C. Final pH of the medium was as low as 3.8 in HCl at 28 d. All strains grew well at pH values lower than the minimum previously reported (5.5–5.6).

GROWTH OF STAPHYLOCOCCUS AUREUS IN ACIDIFIED PASTEURIZED MILK1

1970 ◽  
Vol 33 (11) ◽  
pp. 516-520 ◽  
Author(s):  
T. E. Minor ◽  
E. H. Marth
Keyword(s):  
Staphylococcus Aureus ◽  
Acetic Acid ◽  
Lactic Acid ◽  
Hydrochloric Acid ◽  
Ph Value ◽  
The Other ◽  
Antagonistic Effects ◽  
Pasteurized Milk ◽  
Ph Values ◽  
Effect On Growth

The effect of gradually reducing the pH of pasteurized milk with acetic, citric, hydrochloric, lactic, and phosphoric acids over periods of 4, 8, and 12 hr on growth of Staphylococcus aureus 100 in this substrate was determined. In addition, 1: 1 mixtures of lactic acid and each of the other acids, and of acetic and citric acids were evaluated for their effect on growth of this organism. To achieve a 90% reduction in growth over a 12 hr period, a final pH value of 5.2 was required for acetic, 4.9 for lactic, 4.7 for phosphoric and citric, and 4.6 for hydrochloric acid. A 99% reduction during a 12 hr period was obtained with a final pH value of 5.0 for acetic, 4.6 for lactic, 4.5 for citric, 4.1 for phosphoric, and 4.0 for hydrochloric acid. A pH value of 3.3 was required for a 99.9% reduction with hydrochloric acid, whereas the same effect was produced at a pH value of 4.9 with acetic acid. Correspondingly lower pH values were required to inhibit growth within 8 and 4 hr periods. Mixtures of acids adjusted to pH values at the borderline for growth (12 hr period) exhibited neither synergistic nor antagonistic effects between two acids.

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