scholarly journals N,N’-Bis(salicylidene)ethylenediamine (Salen) as an Active Compound for the Recovery of Ni(II), Cu(II), and Zn(II) Ions from Aqueous Solutions

Membranes ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 60
Author(s):  
Katarzyna Witt ◽  
Daria Bożejewicz ◽  
Małgorzata A. Kaczorowska
Keyword(s):  
Aqueous Solutions ◽  
Metal Ions ◽  
Active Compound ◽  
Metal Ion ◽  
High Resolution Mass Spectrometry ◽  
Separation Of Metal Ions ◽  
Ion Separation ◽  
Liquid Liquid Extraction ◽  
The Stability ◽  
Complexes With Metal Ions

In this paper, three main methods of metal ion separation, i.e., liquid–liquid extraction, transport across polymer inclusion membranes (PIMs), and sorption/desorption, are described. In all of them, N,N’-bis(salicylidene)ethylenediamine (salen) was used as an active compound, i.e., as an extractant or as a carrier for the recovery of Ni(II), Cu(II), or Zn(II) ions from aqueous solutions. In each case, the recovery was performed on a model solution, which contained only a single metal ion. The obtained results were compared with the author’s previous results for the separation of metal ions using β-diketones, since both β-diketones and salen form the so-called Werner-type complexes. Electrospray ionization high-resolution mass spectrometry (ESI-HRMS) was also applied to confirm the ability of the carrier to form complexes with metal ions in a solution. Moreover, spectrophotometry was used to determine the stability constant of the obtained complexes.

scholarly journals Efficient Recovery of Noble Metal Ions (Pd2+, Ag+, Pt2+, and Au3+) from Aqueous Solutions Using N,N'-Bis(salicylidene)ethylenediamine (Salen) as an Extractant (Classic Solvent Extraction) and Carrier (Polymer Membranes)

Membranes ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 863
Author(s):  
Katarzyna Witt ◽  
Małgorzata A. Kaczorowska ◽  
Daria Bożejewicz ◽  
Włodzimierz Urbaniak
Keyword(s):  
Aqueous Solutions ◽  
Metal Ions ◽  
Noble Metal ◽  
High Resolution Mass Spectrometry ◽  
Polymer Membranes ◽  
Single Component ◽  
Molar Ratio ◽  
Efficient Recovery ◽  
The Stability ◽  
Precious Metal Ions

This paper presents the results of the first application of N,N'-bis(salicylidene)ethylenediamine (salen) as an extractant in classical liquid–liquid extraction and as a carrier in membrane processes designed for the recovery of noble metal ions (Pd2+, Ag+, Pt2+, and Au3+) from aqueous solutions. In the case of the utilization of membranes, both sorption and desorption were investigated. Salen has not been used so far in the sorption processes of precious metal ions. Recovery experiments were performed on single-component solutions (containing only one type of metal ions) and polymetallic solutions (containing ions of all four metals). The stability constants of the obtained complexes were determined spectrophotometrically. In contrast, electrospray ionization high-resolution mass spectrometry (ESI-HRMS) was applied to examine the elemental composition and charge of the generated complexes of chosen noble metal ions and salen molecules. The results show the great potential of N,N'-bis(salicylidene)ethylenediamine as both an extractant and a carrier. In the case of single-component solutions, the extraction percentage was over 99% for all noble metal ions (molar ratio M:L of 1:1), and in the case of a polymetallic solution, it was the lowest, but over 94% for platinum ions and the highest value (over 99%) for gold ions. The percentages of sorption (%Rs) of metal ions from single-component solutions using polymer membranes containing N,N'-bis(salicylidene)ethylenediamine as a carrier were highest after 24 h of the process (93.23% for silver(I) ions, 74.99% for gold(III) ions, 69.11% and 66.13% for palladium(II) and platinum(II) ions, respectively), similar to the values obtained for the membrane process conducted in multi-metal solutions (92.96%, 84.26%, 80.94%, and 48.36% for Pd(II), Au(III), Ag(I), and Pt(II) ions, respectively). The percentage of desorption (%Rdes) was very high for single-component solutions (the highest, i.e., 99%, for palladium solution and the lowest, i.e., 88%, for silver solution), while for polymetallic solutions, these values were slightly lower (for Pt(II), it was the lowest at 63.25%).

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 Application of Hydrophobic Alkylimidazoles in the Separation of Non-Ferrous Metal Ions across Plasticised Membranes—A Review

Membranes ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 331 ◽  
Author(s):  
Malgorzata Ulewicz ◽  
Elzbieta Radzyminska-Lenarcik
Keyword(s):  
Mechanical Properties ◽  
Metal Ions ◽  
Metal Ion ◽  
Chemical Resistance ◽  
Ferrous Metal ◽  
Morphological Structure ◽  
Imidazole Ring ◽  
Review Of The Literature ◽  
Separation Of Metal Ions ◽  
The Stability

Currently, a lot of attention is paid to polymer inclusion membranes (PIMs). Their particular advantages include effective support fixation, easy preparation, versatility, stability, good mechanical properties and good chemical resistance. The paper presents a review of the literature related to the applications of polymer inclusion membranes containing alkylimidazole derivatives as carriers in the processes of transporting ions of heavy and toxic metals, such as Zn(II), Cu(II), Cd(II), Co(II), Ni(II), and Mn(II). It has been proven that alkylimidazoles exhibit varying complex-forming properties towards metal ions, and that their properties (hydrophobic and alkaline) can be modified easily by changing the size of the alkyl group and its position in the imidazole ring, which allows obtaining efficiently working metal ion carriers. The stability of an imidazole derivative-metal ion complex determines the speed and selectivity of the process of transporting metal ions across polymer inclusion membranes. Also, the morphological structure of polymer inclusion membranes impacts the efficiency of the process involving the release and separation of metal ions.

The stability constants of ethylenediphosphinetetraacetate complexes

1982 ◽  
Vol 47 (4) ◽  
pp. 1078-1085 ◽  
Author(s):  
Jana Podlahová ◽  
Jaroslav Podlaha
Keyword(s):  
Aqueous Solutions ◽  
Metal Ions ◽  
Stability Constants ◽  
Metal Ion ◽  
Computer Programs ◽  
Data Treatment ◽  
Relative Affinity ◽  
Stability Constants Of Complexes ◽  
Soft Metal ◽  
The Stability

The stability constants of complexes formed by the anions of ethylenediphosphinetetraacetic acid and the metal ions Cu(I), Ag(I), Ca(II), Mn(II), Fe(II), Co(II), Ni(II), Zn(II), Cd(II), Hg(II), Pb(II) and La(III) were determined by various methods (mainly potentiometry and UV-VIS spectrophotometry), followed by data treatment using standard computer programs. The type and stability of the complexes formed depend mostly on the relative affinity of the particular metal ion for the two donor groups of the ligand. Unlike EDTA, the ligand is highly selective for soft metal ions, whose complexes are very stable even in strongly acidic aqueous solutions.

scholarly journals Acylated Anthocyanins from Red Cabbage and Purple Sweet Potato Can Bind Metal Ions and Produce Stable Blue Colors

2021 ◽  
Vol 22 (9) ◽  
pp. 4551
Author(s):  
Julie-Anne Fenger ◽  
Gregory T. Sigurdson ◽  
Rebecca J. Robbins ◽  
Thomas M. Collins ◽  
M. Mónica Giusti ◽  
...  
Keyword(s):  
Metal Ions ◽  
Sweet Potato ◽  
Metal Binding ◽  
Metal Ion ◽  
High Resolution Mass Spectrometry ◽  
Large Set ◽  
Water Addition ◽  
Red Cabbage ◽  
Aluminum Ions ◽  
Purple Sweet Potato

Red cabbage (RC) and purple sweet potato (PSP) are naturally rich in acylated cyanidin glycosides that can bind metal ions and develop intramolecular π-stacking interactions between the cyanidin chromophore and the phenolic acyl residues. In this work, a large set of RC and PSP anthocyanins was investigated for its coloring properties in the presence of iron and aluminum ions. Although relatively modest, the structural differences between RC and PSP anthocyanins, i.e., the acylation site at the external glucose of the sophorosyl moiety (C2-OH for RC vs. C6-OH for PSP) and the presence of coordinating acyl groups (caffeoyl) in PSP anthocyanins only, made a large difference in the color expressed by their metal complexes. For instance, the Al3+-induced bathochromic shifts for RC anthocyanins reached ca. 50 nm at pH 6 and pH 7, vs. at best ca. 20 nm for PSP anthocyanins. With Fe2+ (quickly oxidized to Fe3+ in the complexes), the bathochromic shifts for RC anthocyanins were higher, i.e., up to ca. 90 nm at pH 7 and 110 nm at pH 5.7. A kinetic analysis at different metal/ligand molar ratios combined with an investigation by high-resolution mass spectrometry suggested the formation of metal–anthocyanin complexes of 1:1, 1:2, and 1:3 stoichiometries. Contrary to predictions based on steric hindrance, acylation by noncoordinating acyl residues favored metal binding and resulted in complexes having much higher molar absorption coefficients. Moreover, the competition between metal binding and water addition to the free ligands (leading to colorless forms) was less severe, although very dependent on the acylation site(s). Overall, anthocyanins from purple sweet potato, and even more from red cabbage, have a strong potential for development as food colorants expressing red to blue hues depending on pH and metal ion.

Removal of Pb(II) and Cd(II) From Aqueous Solution by Adsorption Using Agrowaste-Modified Kaolinite Clay

2021 ◽  
Keyword(s):  
Aqueous Solution ◽  
Aqueous Solutions ◽  
Metal Ions ◽  
Metal Ion ◽  
Low Cost ◽  
Ion Concentration ◽  
Kaolinite Clay ◽  
Adsorbent Surface ◽  
Initial Adsorption ◽  
Adsorption Rates

This study showed that kaolinite clay modified with Moringa oleifera pods is a promising low cost adsorbent for the removal of metals from aqueous solution because the resultant composite has higher adsorption capacities, and hence a better metal ions removal efficiency. The efficiencies of these adsorbents for the removal of Pb (II) and Cd (II) ions from aqueous solutions were studied as a function of pH, time, adsorbate concentration and adsorbent dose. Adsorption results showed that pH did significantly affect removal of heavy metal ions between pH 3 and 6. Increasing contact time and initial metal ion concentration increased the sorption capacity of the adsorbent for the metal ions. Adsorbent dosage indicated mainly surface phenomena involving sharing of electrons between the adsorbent surface and the metal ion species. The adsorption of metal ions from aqueous solutions of both metal ions at different initial metal ion concentrations reduced the initial adsorption rates of the adsorption of Pb (II) and Cd (II) by unmodified and modified kaolinite clay.

scholarly journals Inhibition of enzymes by metal ion-chelating reagents. Theory and new graphical methods of study

1974 ◽  
Vol 137 (1) ◽  
pp. 55-60 ◽  
Author(s):  
William G. Bardsley ◽  
Robert E. Childs
Keyword(s):  
Stability Constant ◽  
Metal Ions ◽  
Metal Ion ◽  
Graphical Methods ◽  
Ligand Interaction ◽  
Mechanism Of Inhibition ◽  
The Stability ◽  
Chelating Reagents

1. The mechanism of inhibition of enzymes by metal ion-chelating reagents is discussed and equations derived. 2. Two distinct mechanisms are postulated and graphical methods are given for differentiating between them. 3. Where the metal ion is actually removed from the enzyme to form a co-ordination complex in solution, a procedure is described for obtaining the stability constant for metal–enzyme interaction, the number of metal ions involved and the stoicheiometry of metal ion–ligand interaction.

The affinity of aldehydic compounds to complex formation. Nickel(II) and cobalt(II) complexes with 2-pyridinecarboxaldehyde

1977 ◽  
Vol 55 (14) ◽  
pp. 2613-2619 ◽  
Author(s):  
M. S. El-Ezaby ◽  
M. A. El-Dessouky ◽  
N. M. Shuaib
Keyword(s):  
Complex Formation ◽  
Aqueous Solutions ◽  
Stability Constants ◽  
Metal Ion ◽  
Experimental Conditions ◽  
Complex Species ◽  
Spectrophotometric Methods ◽  
Complex Equilibria ◽  
The Stability ◽  
Hydroxy Groups

The interactions of Ni(II) and Co(II) with 2-pyridinecarboxaldehyde have been investigated in aqueous solutions at μ = 0.10 M (KNO3) at 30 °C. The stability constants of different complex equilibria have been determined using potentiometric methods. Spectrophotometric methods were also used in the case of the nickel(II) – 2-pyridinecarboxaldehyde system. It was concluded that nickel(II) and cobalt(II), analogous to copper(II), enhance hyrdation of 2-pyridinecarboxaldehyde prior to deprotonation of one of the geminal hydroxy groups. Complex species of 1:1 as well as 1:2 metal ion to ligand composition exist under the experimental conditions used.

scholarly journals (96) Color Generation in Hydrangea Sepals as Controlled by Metal Ion Complexes

HortScience ◽  
2005 ◽  
Vol 40 (4) ◽  
pp. 1046C-1046
Author(s):  
Henry D. Schreiber ◽  
Timothy Berry ◽  
Nam Trant
Keyword(s):  
Oxalic Acid ◽  
Metal Ions ◽  
Metal Ion ◽  
Color Change ◽  
Heat Of Solution ◽  
Acid Complex ◽  
Color Changes ◽  
Weak Complexes ◽  
Neutral Soil ◽  
Complexes With Metal Ions

The sepals of many hydrangea cultivars change color from red in basic/neutral soil to blue in acidic soil. This change is generally attributed to Al(III) becoming mobile in acidic soils, allowing it to be absorbed through the roots as a citric acid complex; the ion of Al(III) then forms a blue complex in the sepals with an anthocyanin that is red in the absence of Al(III). This study investigated selected metal ions that might also result in similar color changes in hydrangea sepals. Model anthocyanins such as cyanidin and delphinidin glucoside readily formed blue complexes with metal ions with a high charge/size ratio [that is: Mo(VI), U(VI), and Zr(IV), in addition to Al(III)]. The anthocyanins only formed weak complexes with Fe(III) and Ga(III), and no complexes with Mg(II) and Mn(II). In order for the color change to occur in the sepals, though, the hydrangea must first be able to selectively concentrate the metal ion in the plant from the soil as a complex with citric or oxalic acid. The complexation of Al(III) with the organic acid is shown by the measurement of the heat of solution of citric and oxalic acid in Al(III) solutions as half that of the acids in just water. The presence of Al(III) also enhanced the solubility of oxalic acid in water. Mo(VI) likewise enhanced the organic acid's solubility, while Fe(III), Fe(II), and U(VI) did not appreciably affect the solubility. Mo(VI) and similar ions may be candidates to artificially induce bluing of hydrangea sepals, instead of the current use of Al(III).

Sign in / Sign up

Export Citation Format

Share Document