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1

Reactivity of nZVI in the removal of Cu(II) and Zn(II) from synthetic mine drainage

Suponik Tomasz, Neculita Carmen Mihaela

Environment Protection Engineering

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2021

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Vol. 47, nr 2

93--108

EN

Adsorption properties, including isotherms and kinetics, of nano zero-valent iron (nZVI) for Cu(II) and Zn(II) removal from synthetic mine drainage were evaluated in batch tests. The influence of contact time, nZVI doses, pH, ionic strength, temperature, and concentration on nZVI adsorption properties was assessed. The removal of Cu(II) and Zn(II) increased with pH from 3 to 7 and then stabilized up to pH 10. Moreover, the increased Cu(II) adsorption capacity upon increasing temperature and a positive enthalpy change (ΔH) indicate that the adsorption process is endothermic. The results also showed that the adsorption equilibrium for Cu(II) and Zn(II) was achieved after 50 and 30 min, respectively. Kinetics were best described by a pseudo-nth order model, with the order of sorption of 2.231 and 1.363, and the rate constants of 0.0008 and 0.0679 mg1-n·gn-1/min, for Cu(II) and Zn(II), respectively. The correlation between the amount of metals adsorbed on nZVI surface and the residual amount of metals in water during isothermal tests was best described by the nonlinear Sips model. Using this model, high q maxS were found: 286.6 mg/g and 142.6 mg/g, for Cu(II) and Zn(II), respectively, as indication of their high sorption capacity.

2

Otrzymywanie, spektroskopia i biologiczna aktywność kompleksów Cu(II) i Zn(II) z pochodnymi 1,3,4-tiadiazolu

Karcz D., Starzak K., Matwijczuk A., Ciszkowicz E., Lecka-Szlachta K., Matwijczuk A., Ciupak A., Gładyszewska B., Niewiadomy A.

Przemysł Chemiczny

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2018

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T. 97, nr 7

1095--1101

PL

Stosując łagodne warunki reakcji, otrzymano dwa nowe kompleksy Cu(II) i Zn(II) z ligandem wyselekcjonowanym z pochodnych 1,3,4-tiadiazolu. Wszystkie substancje scharakteryzowano z zastosowaniem metod spektroskopowych i oszacowano zakres ich aktywności biologicznej poprzez wyznaczenie potencjału przeciwutleniającego i aktywności przeciwbakteryjnej przeciw kilku szczepom bakterii. W porównaniu z uprzednio opisywanymi pochodnymi z tej serii związków otrzymane kompleksy z jonami Cu(II) i Zn(II) charakteryzowały się relatywnie wysoką rozpuszczalnością w roztworach wodnych. Ponadto otrzymane związki wykazały zadowalającą aktywność antyoksydacyjną i umiarkowaną aktywność przeciwbakteryjną.

EN

Two novel Cu(II) and Zn(II) complexes with 1,3,4-thiadiazoles were obtained under mild reaction conditions. The structures of free ligands and the corresponding complexes were characterized by spectroscopic methods. The biol. activity of all compds. was estd. by detn. of their antioxidant and antibacterial activities against bacterial species. The complexes showed relatively high soly. in aq. solns. Both the free ligands and their Cu(II) and Zn(II) complexes exhibited a moderate antioxidant and antibacterial activities.

3

Adsorption behavior of Zn(II) onto natural minerals in wastewater. A comparative study of bentonite and kaolinite

Chai W., Huang Y., Su S., Han G., Liu J., Cao Y.

Physicochemical Problems of Mineral Processing

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2017

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Vol. 53, iss. 1

264--278

EN

In order to remove the harmful metal ions in lead-zinc mineral processing wastewater, two natural clay minerals (bentonite and kaolin) were used as adsorbents and Zn(II) ions were the emphasis in this work. The adsorption behaviors including kinetics and isotherms were investigated by batch experiments. In addition, the adsorption mechanisms were studied by means of zeta potential testing, optical microscope and XRD analysis. The results show that the adsorption process can be best described as the pseudo-second order kinetic model. The adsorption equilibrium data of bentonite and kaolinite can be respectively fitted best by Langmuir and Freundlich models. Thermodynamic studies display that the adsorption of Zn(II) onto clays is non-spontaneous and endothermic. The maximum capacity of Zn(II) adsorbed on bentonite and kaolinite respectively reaches to 79.2 mg·g-1 and 6.35 mg·g-1 at 25 °C. The structural differences of bentonite and kaolinite result in the differences in adsorption behavior and mechanism. The interaction mechanisms of Zn(II) with bentonite and kaolinite involve electrostatic attraction, cation exchange, surface complex and precipitation. Bentonite as adsorbent has the potential to remove Zn2+ better than kaolinite.

4

Kinetics and isotherm modelling of Zn(II) ions adsorption onto mine soils

Jalayeri H., Salarirad M. M., Ziaii M.

Physicochemical Problems of Mineral Processing

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2016

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Vol. 52, iss. 2

767--779

EN

The soils consist of various components that can play a significant role in control of heavy metals in the environment. Therefore, understanding of adsorption properties of soil is essential in solving pollution problems around mine sites. The goal of this paper is to study Zn(II) ions adsorption onto copper mine soil. Soils were examined via X-ray diffraction and scanning electron microscopy. The influence of various parameters such as effect of pH, adsorbent dose, and initial concentration of Zn(II) ions on adsorption was evaluated by batch method. The adsorption isotherms of Zn(II) ions such as Langmuir, Freundlich, and Temkin were studied. The Langmuir isotherm indicated an excellent fit for the experimental data in comparison with other isotherms that shown monolayer adsorption onto a homogenous surface. A number of kinetic models were tested to fit the kinetic data. The results show that soils can be more effective in decreasing heavy metals contamination specially Zn(II) ions from solution phase.

5

Adsorption of Zn(II) ions from aqueous environment by surface modified Strychnos potatorum seeds, a low cost adsorbent

Senthil Kumar P.

Polish Journal of Chemical Technology

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2013

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Vol. 15, nr 3

35-41

EN

The surface modified Strychnos potatorum seeds (SMSP), an agricultural waste has been developed into an effective adsorbent for the removal of Zn(II) ions from aqueous environment. The Freundlich model provided a better fit with the experimental data than the Langmuir model as revealed by a high coefficient of determination values and low error values. The kinetics data fitted well into the pseudo-second order model with the coefficient of determination values greater than 0.99. The influence of particle diffusion and film diffusion in the adsorption process was tested by fitting the experimental data with intraparticle diffusion, Boyd kinetic and Shrinking core models. Desorption experiments were conducted to explore the feasibility of regenerating the spent adsorbent and the adsorbed Zn(II) ions from spent SMSP was desorbed using 0.3 M HCl with the efficiency of 93.58%. The results of the present study indicates that the SMSP can be successfully employed for the removal of Zn(II) ions from aqueous environment.

6

Porównanie przebiegów równolegle zachodzących flotacji jonów cynku i miedzi

Kawalec-Pietrenko B., Konopacka-Łyskawa D., Rybarczyk P.

Inżynieria i Aparatura Chemiczna

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2011

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Nr 5

50-51

PL

W pracy zbadano wpływ pil oraz stężenia kolektora na efektywność procesów flotacji jonowej i precypitacyjncj zastosowanych do równoległego usuwania jonów cynku Zn(II) i miedzi Cu(II) z rozcieńczonych, kwaśnych i alkalicznych roztworów wodnych. Najwyższe wartości stopnia wyfloto-wania dla obydwu metali odnotowano dla pll = 8,5 + 9,5 przy zastosowaniu SDS jako kolektora. Dla roztworów o pH> 11 zaobserwowano spadek stopnia wyflotowania ze wzrostem stężenia kolektora kationowego oraz wystąpienie czasu indukcji.

EN

An influence of pH and collector concentration on the precipitation and ion flotation efficiency used for removal of Zn(ll), Cu(II) ions from diluted, acidic and alkaline water solutions was tested. The highest values of flotation degree were noted for pH= 8.5 9.5 and for SDS used as a collector. For solutions of pH> 11, it was observed the decrease of flotation degree with the increase of cationic collector concentration and the presence of induction time.

7

Crystal structure and spectroscopic properties of [Zn(2-qmpe)Cl2] containing diethyl (quinolin-2-ylmethyl)phosphonate ligand (2-qmpe)

Żurowska B., Białońska A., Kotyński A., Ochocki J.

Materials Science Poland

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2010

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Vol. 28, No. 2

573--581

EN

The crystal structure of [Zn(2-qmpe)Cl2] (2-qmpe, diethyl (quinolin-2-ylmethyl) phosphonate) ligand) was determined by X-ray-diffraction. The compound was also characterized by IR, far-IR, 1H and 31P NMR spectroscopy. In the molecule, 2-qmpe acts as a bidentate N,O-chelate ligand. Tetrahedral ZnNOCl2 environment of Zn(II) atom is slightly distorted. The structure is stabilized by intermolecular H bond and n---n interactions. The spectral features are in agreement with the structural data.

8

The Synthesis and Characterization of (1Z,2Z)-N~1~,N~2~Dihydroxy-N~1~,N~2~ dipyridin-2-ylethanedimidamide and Its Mono and Dinuclear Zn(II), Cd(II) and Hg(II) Complexes

Kakanejadifard A., Niknam E.

Polish Journal of Chemistry

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2006

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Vol. 80, nr 10

1651-1656

EN

The novel Schiff base ligand, 4-methoxysalicyliden-p-aminoacetophenoneoxime (LH) was synthesized starting from p-aminoacetophenoneoxime and 4-methoxysalicylaldehyde. Mononuclear cobalt(II), copper(II) and zinc(II) complexes of the ligand have been prepared by using Co(II), Cu(II) and Zn(II) salt with a metal to ligand ratio of 1:2. The structures of the ligand and its complexes were identified by using elemental analyses, IR, 1H- and 13C-NMR spectra, magnetic susceptibility measurements, UV spectra and thermogravimetric analyses (TGA).

9

Transport jonów Zn(II) i Pb(II) przez polimerowe membrany inkluzyjne zawierające kwasy fosforoorganiczne w roli przenośników jonów

Ulewicz M., Gajda B.

Hutnik, Wiadomości Hutnicze

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2006

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Vol. 73, nr 7

317-321

PL

W pracy przedstawiono wyniki badań transportu jonów Zn(II) i Pb(II) przez polimerowe membrany inkluzyjne. W roli przenośnika jonów zastosowano kwas di(2-etyloheksylo)fosforowy oraz komercyjne przenośniki Cyanex 272, 302 i 302. Przedstawiono wpływ rodzaju i stężenia przenośnika, pH fazy zasilającej oraz stężenia kwasu w fazie odbierającej na efektywność i selektywność procesu transportu kationów.

EN

In this paper the facilitated transport of Zn(II) and Pb(II) ions through polymer inclusion membranes is presented. In membranes di(2-ethylhexyl)phosphoric acid (D2EHPA ) as well as commercial extractants, i.e. Cyanex 272, 301, and 302 were used as ion carrier. The infl uence of the carrier nature and concentration in the membrane phase and pH receiving phase, and concentration of HCl in receiving phase on cation transport selectivity end effi ciency has been shown.

10

Adsorptional removal of chemical pollutants on active carbons

Sarbak Z., Ners M.

Chemia i Inżynieria Ekologiczna

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2004

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Vol. 11, nr 10

1055--1063

EN

Results of a study on adsorption properties of active carbon made by four different producers: Gryfskand in Hajnówka, Carbon Ltd. in Racibórz, Chemviron Carbon and Norit N.V. have been reported. All the products have been found active in heavy metal removal. Their effectiveness depends on the type of coal and concentration of ions in solution and type of the metal ions to be removed. The effectiveness of adsorptional removal of Cr(lII) is much lower than that of Zn(II) and Cd(II), which follows from lower accessibility of the hexaaquaions [Cr(H2O)6]3+ to the adsorption centres in the micropores. The same holds true for the Cr2O7-2 ions. The tests for adsorption of n-butylamine have shown that only some types of carbon are effective in adsorbing it. Taking into regard that n-butylamine has a free electron pair on the nitrogen atom the results of the tests indicate that the effectiveness of its adsorption depends on the number and strength of the acidic centres at the surface of the active carbons studied.

PL

Przedstawiono wyniki badań nad właściwościami adsorpcyjnymi węgli aktywnych wyprodukowanych przez Hajnowskie Przedsiębiorstwo Suchej Destylacji Węgla - obecnie Gryfskand, Carbon Sp. z 0.0. w Raciborzu, Chemviron, Carbon S.A. oraz Nont N.V. Stwierdzono, że badane preparaty wykazywały aktywnośćw usuwaniu jonów metali ciężkich. Efektywność ich usuwania jest zróżnicowana i zależy od rodzju węgla i stężenia jonów w roztworze oraz od rodzaju jonu metalicznego. W przypadku jonów Cr(III) efektywność w ich adsorpcyjnym usuwaniu jest znacznie mniejsza w porównaniu do adsorpcji jonów Zn(II) i Cd(II), co spowodowane jest mniejszą dostępnością heksaakwajonów [Cr(H2O)6]3+ do centrów adsorpcyjnych mieszczących się w mikroporach. Podobne stwierdzenie dotyczy aktywności adsorpcyjnej badanych próbek w stosunku do jonów Cr2O7-2. W przypadku adsorpcji n-butyloaminy wykazano, że bardzo dużą aktywność mają tylko niektóre rodzaje węgli aktywnych. Biorąc pod uwagę właściwości chemiczne n-butyloaminy związane z istnieniem wolnej pary elektronowej na atomie azotu, należy sądzić, że decydujące znaczenie będzie miała liczba i moc centrów kwasowych związanych z powierzchnią badanych węgli.

11

The Synthesis and Characterization of 1,2-dihydroxyimino-3,6-di-aza-8,9-O-iso-butylidene Nonane and Its Complexes with Ni(II), Cu(II), Zn(II) and Cd(II)

Canpolat E., Kaya M., Görgülü A. O.

Polish Journal of Chemistry

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2002

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Vol. 76 / nr 5

687-694

EN

1,2-Dihydroxyimino-3,6-di-aza-8,9-O-iso-butylidene nonane (H2L) was synthesized starting from 1,2-O-iso-butylidene-4-aza-6-amino hexane (RNH2) and antichloroglyoxime. Ni(II) and Cu(II) complexes ofH2L have a metal:ligand ratio of 1:2 and the ligand coordinates through two N atoms, as do most of the vic-dioximes. However, Zn(II) and Cd(II) complexes of H2L have a metal:ligand ratio of 1:1 and one chloride ion and one water molecule are also coordinated to the metal ion. Structures of the ligand and its transition- metal complexes are proposed, according to elemental analyses, IR, 13C and 1H NMR spectra, magnetic susceptibility measurements and thermogravimetric analyses (TGA).