The State of Metal Ion in Aqueous Solutions and its Surface Chemical Effect. II. Uptake of Metal Ions from Aqueous Solutions by Stearic Acid Monolayer

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.

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Removal of Pb(II), Zn(II), Sn(II) and Cu(II) Ions from Aqueous Solutions by Linear Alternating Poly(4,4'-biphenol oxalate) Oligomer

Jordan Journal of Chemistry ◽

10.47014/15.2.3 ◽

2020 ◽

Vol 15 (2) ◽

pp. 73-85

Keyword(s):

Aqueous Solutions ◽

Metal Ions ◽

Metal Ion ◽

Ph Value ◽

Equilibrium Concentration ◽

Ion Uptake ◽

Uptake Capacity ◽

Concentration Data ◽

Hno3 Solution ◽

Metal Ion Uptake

Poly(4,4′-biphenol oxalate) oligomer was synthesized and characterized by FT-IR, elemental analysis XRD and thermal analysis. The capability of the oligomer to take away Pb(II), Zn(II), Sn(II) and Cu(II) metal ions from aqueous solutions was considered by the known batch and column techniques in terms of concentration, pH value, contact time and temperature. The results indicated that a high initial rate of metal-ion uptake by the oligomer was observed throughout the first 30 minutes, which enlarged slightly amid rising the pH value and then reached its greatest value at pH=5.00 for Pb(II) and Zn(II), pH=4.00 for Cu(II) and pH=6.00 for Sn(II). The oligomer exhibited a high metal-ion uptake capacity to Pb(II) and Zn(II), but a little metal-ion uptake capacity to Cu(II) and Sn(II). Linearized forms of the Langmuir, Freundlich and Dubinin–Radushkevich adsorption isotherms were used to investigate the experimental equilibrium concentration data of Pb(II), Zn(II), Cu(II) and Sn(II). ΔG values demonstrated that the adsorption process of these metal ions on the oligomer is favored while the ΔH values indicated that this process is endothermic. On the other hand, the entropy of the process is positive. In addition to batch experiments, column experiments were performed, where the metal ions were efficiently recovered by treatment of the metal-loaded oligomer with 1.0 M HNO3, 1.0 M HCl and 0.5 M EDTA. The best results were obtained with 1.0 M HNO3 solution.

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Adsorption properties of a nanostructured hybrid material containing aluminium towards some metal ions

Open Chemistry ◽

10.2478/s11532-011-0080-0 ◽

2011 ◽

Vol 9 (5) ◽

pp. 932-940 ◽

Cited By ~ 1

Author(s):

Albena Detcheva ◽

Paunka Vassileva ◽

Ralitsa Georgieva ◽

Dimitrinka Voykova ◽

Tsvetelina Gerganova ◽

...

Keyword(s):

Aqueous Solutions ◽

Metal Ions ◽

Hybrid Material ◽

Metal Ion ◽

Ph Value ◽

Sol Gel ◽

Transition Metal Ions ◽

Adsorption Properties ◽

Adsorption Of Nitrogen ◽

Pseudo Second Order

AbstractIn the present work the adsorption of some transition metal ions from aqueous solutions on a silica-based nanostructured hybrid material modified by aluminium was investigated. The novel organic-inorganic material was synthesized via a sol-gel method through hydrolysis and co-condensation reactions. Its structure was characterized by means of SEM, XRD and FTIR. Based on the data obtained the most probable cross-linking mechanism for the derived xerogel was proposed. The characterization of its texture parameters was carried out by low-temperature adsorption of nitrogen. The adsorption properties of this material with respect to Cu(II), Cr(III) and Pb(II) ions from single-component aqueous solutions and multi-component aqueous solutions containing also Cd(II) and Fe(III) were evaluated. The effect of contact time, acidity of initial solutions and metal ion concentrations was investigated using the batch method. Pseudo-first order, pseudo-second order and intraparticle diffusion models were used to analyze kinetic data. In all cases the adsorption was significantly affected by the pH value. Equilibrium modelling data were fitted to linear Langmuir, Freundlich and Dubinin-Radushkevich models. Best fit was observed for Langmuir model, which showed determination coefficients greater than 0.992 for all ions studied. The maximum adsorption capacities for single- and multi-component adsorption were calculated.

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Regularities and mechanism of heavy metal cations sorption and (or) proton desorption by chitosan from aqueous solutions

Canadian Journal of Chemistry ◽

10.1139/cjc-2018-0384 ◽

2019 ◽

Vol 97 (8) ◽

pp. 621-628 ◽

Cited By ~ 4

Author(s):

T.E. Nikiforova ◽

V.A. Kozlov ◽

M.K. Islyaikin

Keyword(s):

Heavy Metal ◽

Aqueous Solutions ◽

Metal Ions ◽

Metal Ion ◽

Heavy Metal Ions ◽

Metal Cations ◽

Batch Adsorption ◽

Amino Groups ◽

Acidic Media ◽

Chitosan Beads

The sorption process of heavy metal ions from aqueous solutions using chitosan flakes and chitosan beads was studied. Chitosan gel beads were prepared using covalent crosslinking of chitosan chains by epichlorohydrin with ionic gelation by sodium tripolyphosphate. The capability of chitosan beads to absorb the heavy metal ions from aqueous solutions was studied, and the physicochemical characteristics of the sorbent were evaluated using SEM and FTIR on the model solution treatment. It was found that competitive proton sorption takes place in acidic media, which results in a transformation of amino groups into inactive ammonium-salt form and decreases in heavy metal sorption onto chitosan from aqueous acidic media. Batch adsorption experiments were performed to examine the influence of various factors such as the initial concentration of metal salts, pH, and agitation duration on the process. It was established that metal ion sorption is pH dependent and has an optimum effect at a pH of 6.0. Following the Langmuir equation, the maximum sorption of Cu2+ions is estimated to be 1,6 mol/kg of modified chitosan. The kinetic study revealed that the adsorption kinetics are well-fitted to the kinetic equation of pseudo second order. Thus, sorption of heavy metal ions by chitosan is considered to be a competitive process that occurs on amino groups of the sorbent with equivalent coordinated participation of metal cations, protons, and anions.

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Synthesis of zeolites with different chemical and textural properties for metal ions removal from aqueous solutions

Water Science & Technology ◽

10.2166/wst.2017.508 ◽

2017 ◽

Vol 76 (12) ◽

pp. 3441-3451 ◽

Cited By ~ 3

Author(s):

Danielle França de Oliveira ◽

Jefferson Antoniol Mendes Neri ◽

Jonas Alves de Almeida Ribeiro ◽

Fabiana Soares dos Santos ◽

Mendelssolm Kister de Pietre

Keyword(s):

Aqueous Solutions ◽

Metal Ions ◽

Surface Area ◽

Metal Ion ◽

Active Sites ◽

Chemical Interaction ◽

Textural Properties ◽

Lead Ion ◽

Metal Ion Removal ◽

Β Zeolite

Abstract In this study β-zeolite, ferrierite and partially delaminated PREFER (precursor of ferrierite) zeolites with several chemical and textural properties were synthesized for the removal of zinc and lead ion metals from their respective solutions. Adsorption experiments involving the suspension of tiny amounts of these solids in aqueous solutions containing either Zn2+ or Pb2+ showed that the removal of these metals at a considerable extent may be attained. Among the studied materials, β-zeolite displayed the better performance in metal ion removal, which may be ascribed to its higher aluminum content, surface area and external surface area, that allows a greater density and availability of ion adsorption active sites. Kinetic data from a pseudo-second-order model indicate that the chemical interaction among metal ions and active sites is the rate-limiting step. Furthermore, the better performance of the β-zeolite displayed in reusability testing makes it a potential adsorbent for future applications in the treatment of effluents containing toxic metals.

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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 ◽

10.3390/membranes10040060 ◽

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.

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The stability constants of ethylenediphosphinetetraacetate complexes

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19821078 ◽

1982 ◽

Vol 47 (4) ◽

pp. 1078-1085 ◽

Cited By ~ 10

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.

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Ionic liquids as selective extractants and ion carriers of heavy metal ions from aqueous solutions utilized in extraction and membrane separation

Reviews in Chemical Engineering ◽

10.1515/revce-2014-0048 ◽

2015 ◽

Vol 31 (2) ◽

Cited By ~ 36

Author(s):

Beata Pospiech ◽

Wojciech Kujawski

Keyword(s):

Ionic Liquids ◽

Aqueous Solutions ◽

Metal Ions ◽

Metal Ion ◽

Membrane Separation ◽

Research Area ◽

Separation Processes ◽

Removal Of Heavy Metals ◽

Heavy Metals Ions

AbstractThis paper analyzes the applications of various ionic liquids (ILs) as metal ion carriers and extractants utilized for the separation of metal cations from aqueous solutions. Subsequently, an up-to-date review of the use of ILs in polymer inclusion membranes is presented. ILs represent a promising group of extractants and ion carriers of metal ions in extraction and membrane separation processes. The removal of heavy metals ions from aqueous solutions using ILs indicates an extensive and promising research area. It is expected that the role of ILs will gradually increase as the worldwide implementation of separation methods in recovery of metal ions from various aqueous solutions is growing quickly.

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