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1

The Effects of Diluents on Sodium Ion Transport through Bulk Liquid Membrane with Crown Ether Carriers

Altin S., Peker I., Demircioglu N.

Polish Journal of Chemistry

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2009

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Vol. 83, nr 2

275-283

EN

In this study, the effects of the different mebrane diluents, carriers and variations in the concentrations of the carriers on the sodium ion transport were examined in bulk liquid mebrane systems. The kinetic analysis of the sodium ion transport in the liquid membrane was performed through the implementation of two consecutive kinetic equations of first order irreversible reactions and the relevant kinetic parameters (k1, k2a, k2m, Rmax, tmax) were determined. Toluene, n-hexane, 1-octanol, chloroform and dichloromethane were used as membrane diluents, while 18crown6 (18C6), dicyclohexyl 18crown6 (DC18C6) and dibenzo 18crown6 (DB18C6) were used as carriers. The results reveal that the best sodium ion transport was realized when toluene-dichloromethane (90%-10%) was used as the membrane, and 1×10-3 M DB18C6 was used as the carrier.

2

Zastosowanie eterów koronowych w procesie transportu jonów Zn(II), Cd(II) I Pb(II) przez polimerowe membrany inkluzyjne

Ulewicz M.

Przemysł Chemiczny

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2008

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T. 87, nr 2

210-213

3

Conductance Study of the Complexation of NH4+ and Tl+ Ion with Different Crown Ethers in Binary Acetonitrile-Methanol Mixtures

Khayatian G., Karoonian F. S., Vaziri S.

Polish Journal of Chemistry

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2008

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Vol. 82, nr 3

537-545

EN

A conductance study of the interaction of NH4 + and Tl+ ion with 18-crown-6 (18C6), ditertbutyl-dicyclohexyl-18-crown-6 ((t-but)2DC18C6), diaza-15-crown-5 (DA15C5), dibenzo-21-crown-7 (DB21C7) and dibenzo-24-crown-8 (DB24C8) in acetonitrilemethanol mixture was carried out at 25.0š0.1°C. The formation constants of the resulting 1:1 complexes were determined from the molar conductance-mole ratio data and found to vary in the order of DA15C5 > 18C6 > DB21C7 > (t-but)2DC18C6 > DB24C8, in the case of Tl+ ion in 100% MeOH, and in the order of: DA15C5 > 18C6 > (t-but)2DC18C6 > DB21C7 > DB24C8 for the NH4 + ion in 100% AN and AN-MeOH mix tures. The sta bil i - ties of the complexes for NH4 + and Tl+ ions varied in versely with the Gutmann donicity of the solvent with the ex cep tion of DA15C5-Tl+ complexes. The in fluence of substituents on the polyether ring and cavity size is discussed.

4

The effect of benzene moiety fused with macrocyclic ring on the proton affinity of crown ethers studied in MS/MS experiment

Frański R., Gierczyk B.

Ars Separatoria Acta

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2008

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No. 6

61-68

EN

In this paper we address the question how the presence of an aromatic moiety affects the proton affinity of crown ethers. In order to compare the proton affinities of crown ethers studied (M), we compared the abundances of protonated crown ethers ([M + H]+ ions) with the abundance of the ion [NH2-B15C5 + H]+ (formally also protonated crown ether). Both [M + H]+ and [NH2-B15C5 + H]+ were formed as a result of decomposition of [NH2-B15C5 + H + M]+. The presence of a benzene moiety fused with a macrocyclic ring strongly decreases the ratio [M + H]+/[NH2-B15C5 + H]+. Thus, the higher ring strain caused by the benzene moiety leads to a substantial lowering of the proton affinity of crown ethers. It is also suggested that for protonated benzocrown ethers the ring strain is partly compensated by the proton-đ interaction. The presence of an NO2 group decreases the electron density on the aromatic ring and, consequently, the proton-đ interaction is suppressed. As expected, the proton affinity of benzo-crown ethers increases with increasing size of their cavity since the ring strain is lower for larger molecules. An unexpectedly high proton affinity of dicyclohexano-18-crown-6 (DC18C6) has been observed.

5

Proton - ionizable lariat ethers in ion flotation process - effect of alkali metal cations

Ulewicz M., Maciejewski P.

Ars Separatoria Acta

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2008

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No. 6

53-60

EN

An experimental investigation is presented on flotation of Cs+, Sr2+ and Ba2+ cation metals from dilute aqueous solutions using lariat ethers with a novel protonionizable group in the presence of foaming agent. The influence of concentration of Li+, Na+, K+ (as source of foreign cations) on kinetic rate constant and maximal percent removal was studied. The addition of Li+, Na+, K+ cations (over 1.0ź10-3 mol/dm3) depressed the removal of Cs+, Sr2+ and Ba2+ remarkably, and the removal of floated cations was very low (at the concentration of alkali metal cations – 1.0ź10-2 mol/dm3). The influence of foreign cations on flotation depression increases in the order: K+ < Li+ < Na+. Authors propose the correlation between the maximal percent removal of Cs+, Sr2+ or Ba2+ and concentration of Li+, Na+ or K+ cations in aqueous solution.

6

Lithium-7 NMR and ab initio Calculation Studies of Complexation of Li+ Ion with 12-Crown-4, Benzo-12-crown-4, 15-Crown-5, Benzo-15-crown-5, and Dibenzo-15-crown-5 in Binary Nitromethane-Acetonitrile Mixtures

Shamsipur M., Alizadeh N., Rofouei M. K., Alizadeh K.

Polish Journal of Chemistry

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2007

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Vol. 81, nr 10

1743-1743

EN

Complexes of 12-crown-4 (12C4), benzo-12-crown-4 (B12C4), 15-crown-5 (15C5), benzo-15-crown-5 (B15C5) and dibenzo-15-crown-5 (DB15C5) with Li+ ion were investigated by lithium-7 NMR in a number of nitromethane (NM)-acetonitrile (AN) binary mixtures. In all cases, the exchange between the free and complexed lithium ionwas fast on the NMR time scale and a single population average resonance was observed. Both 1:1 and 2:1 (sandwich) complexeswere observed between lithium ion and 12C4 and B12C4 in pure nitromethane solution. Stepwise formation constants of the 1:1 and 1:2 (metal/ligand) complexes were evaluated from computer fitting of the NMR mole ratio data to equations which relate the observed metal ion chemical shifts to formation constants. There is an inverse linear relationship between the logarithms of the stability constants and the mole fraction of acetonitrile in the solvent mixtures. The stability of the complexes varies inversely with the Gutmann donor number of the solvent. The stability order of the complexes was found to be 15C5.Li+> B15C5.Li+> DB15C5.Li+> 12C4.Li+ > B12C4.Li+. The optimized structures of the free ligands and their 1:1 and 2:1 complexes with Li+ ionwere predicted by ab initio theoretical calculations using theGaussian 98 software, and the results are discussed.

7

Studies on Transport of Pb(II) Ions Using Different Crown Ethers

Ashraf W., Fazal A.

Polish Journal of Chemistry

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2006

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Vol. 80, nr 6

881-887

EN

Membrane based separation processes represent a sophisticated way to limit industrial wastes in the natural environment. Crown ethers have been recognized as very effective class of compounds to achieve selective separation of heavy metal ions from aqueous solutions. Lead (Pb) is a well known toxic metal and is heavily used in industry. Therefore, finding ways to selectively remove Pb(II) from aqueous solutions is important. In the present paper, different crown ethers of varying cavity size, subsituent groups, donor atoms, and ring number are compared for their ability to transport Pb2+ through a supported liquid membrane. All experiments were carried out in a laboratory scale membrane reactor with crown ether solution immobilized on a polypropylene porous sheet interposed between feed and strip solutions. It was observed that when O atoms of the same sized macrocycle are replaced with N or S atoms, percentage recovery of Pb(II) increases significantly. By substituting a benzene ring on the same sized macrocycle, the percentage of Pb(II) transport increased from 78 to 86%. The cavity size of the crown ether seems to affect the rate of transport. After different trials, it was found that transport is maximal where the ionic radius of Pb(II) matches maximum with the cavity diameter of the macrocycle. These interactions of crown ethers with Pb(II) are explained on the basis of metal-ligand coordination chemistry.

8

Textile slow-release systems with medical applications

ten Breteler M. R., Nierstrasz V. A., Warmoeskerken M. M. C. G.

Autex Research Journal

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2002

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Vol. 2, no. 4

175--189

EN

In the development of medical drug delivery systems, attention has been increasingly focused on slow- or controlled delivery systems in order to achieve an optimal therapeutic effect. Since the administration of drugs often requires a defined or minimum effective dosage in the human body, more conventional delivery systems such as tablets require relatively high doses, which can result in undesired toxic effects. Subsequent degradation of the drug in the human body will result in a drug concentration below the minimum effective level. Furthermore, there are situations where oral administration is less advisable, such as in cases of prolonged treatment or with people that are forgetful, which again results in ineffective treatment. Textile slow-release systems have the potential to overcome these negative aspects. Drugs containing transdermal patches for ex-vivo applications are already familiar; however, this paper will not deal with such applications, but with more advanced in-vivo textile slow-release systems. Due to enormous progress over the years in the fields of supramolecular chemistry, nanotechnology, and polymer science & technology, a number of promising drug delivery technologies have been developed. This review will focus on the opportunities of textiles bearing cyclodextrins, aza-crown ethers or fullerenes, as well as ion-exchange fibres, drug-loaded hollow fibres, textiles treated with nanoparticles and fibres with bioactive compounds in their embodiment. In this paper, the delivery systems will be discussed and compared in terms of biostability, biodegradability, controllability, toxicity, carcinogenicity, interface reactions, material costs and the fabrication process.

9

Application of macrocycle compounds for metal ions separation and removal - a review

Walkowiak W., Ulewicz M., Kozłowski C. A.

Ars Separatoria Acta

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2002

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No. 1

87-98

EN

A review is presented on macrocyclic compounds novel reagents for metal ions separation and removal in solvent extraction, transport through liquid membranes, and flotation processes. As macrocyclic compounds were used such chemicals as non-ionizable crown ethers, ionizable crown ethers (lariat ethers), calixarenes, and acyclic polyethers. Many literature data as well our own recent research data will be reported on metal ions removal and separation.

10

The Influence of Structural Effects on the Complexing Ability of Crown Ethers III. Rubidium Complexes Formed by the Ligands of the 18C6 Typ

Filipek S., Krzyśko K., Kalinowski M. K.

Polish Journal of Chemistry

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2001

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Vol. 75, nr 12

1887-1893

EN

A combined AM 1 and molecular mechanics study of the complexation of the rubidium cation by nine substituted crown ethers, L, containing 18 atoms of macroring is presented. The role of microsolvation was incorporated into the models by studying the complexes surrounded by six methanol molecules. The substituent effect is related to the interaction energy, Eint, which was computed for the clusters LRb+(CH3OH)6 in their lowest energy conformations. This is demonstrated by the linear correlation found by plotting logKs vs. Eint, where Ks stands for stability constant of a complex. The appropriate Ks values were calculated on the basis of cyclic voltammetric measurements.

11

Calixarenes as alkali metal ions receptors

Śliwa W.

Chemistry-Didactics-Ecology-Metrology

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2001

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R. 6, NR 1-2

9--15

EN

Selected calixarenes useful as alkali metal ions receptors are described. Calixarenes, calixcrowns and callx-bis-crowns are presented, along with their application possibilities, e.g. radiocesium removal, as well as synthetic approaches.

PL

Opisano wybrane kaliksareny użyteczne jako receptory jonów litowców. Omówiono kaliksareny, kaliksareno-etery koronowe i kaliksareno-bis-etery koronowe, opisujac ich możliwości zastosowań, np. w celu usuwania radiocezu, oraz metody syntezy.

12

Membrane based on decyl-18-crown-6 for a potassium selective sensor

Hopârtean E., Pică E. M., Ana C., Cosma V., Hopârtean I.

Chemia Analityczna

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2001

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Vol. 46, No. 1

41-49

EN

Four kinds of 18-crown-6 derivatives were studied as ionophores in plasticized poly(vi-nyl chloride) (PVC) in order to obtain potassium selective membrane. The properties of the sensor were studied in detail. For the optimization of the selectivity toward K+ over Na+ the influence of the following factors was studied: nature and concentration of the ionophore; nature and concentration of the plasticizer and lipophilic salt addition. The potassium ion-selective membrane electrode was designed. The electrode has a fast and Nernstian response in the 1 x 10(-1)-2 x 10(-5) mol 1(-1) K+, after six months of continuous measurements. The change of pH in the range 2-10.5 does not affect the response of the electrode. The internal resistance of the electrode was measured. The electrode shows a good stability and can be used in the potentiometric determination.

PL

Badano cztery rodzaje pochodnych związku: 18-korona-6 jako jonofory w plastyfi-kowanym polichlorku winylu (PVC), w celu uzyskania membrany selektywnej względem jonów potasowych. Szczegółowo badano własności czujnika pomiarowego. W celu optymalizacji selektywności względem jonów K+ w porównaniu do jonów Na+ zbadano wpływ następujących parametrów: rodzaj i stężenie jonoforu, rodzaj i stężenie plasty-fikatora, oraz dodatek soli lipofilowej. Zaprojektowano jonoselektywną elektrodę membranową, selektywną względem jonów potasowych. Elektroda ma krótki czas odpowiedzi i nernstowską odpowiedź w granicach stężeń: 10(-1) x 10(-5) mol l(-1) K+ po sześciu miesiącach ciągłych pomiarów. Zmiana pH w granicach 2-10.5 nie wpływa na odpowiedź elektrody. Zmierzono wewnętrzną rezystancję elektrody. Elektrodę cechuje dobra trwałość i można ją używać do oznaczeń potencjometrycznych.

13

New lithium selective chromogenic crown ethers

Wagner-Wysiecka E., Luboch E., Kłonkowski A., Biernat J.F.

Biocybernetics and Biomedical Engineering

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2001

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Vol. 21, no. 4

67-85

EN

New proton-dissociable crown compounds resembling mordant azo dyes were prepared and investigated. Molecules of the chromoionophores constitute of: polyoxyethylene residues and two azo chromophores forming macrocycle, and phenolic OH residue. As a proton dissociable group also azole NH groups were chosen. Many of the compounds are valuable reagents for recognition of lithium cations with largc separations of spectral bands for the ligands and their complexes with alkali metal cations. Derivatives of phenols and resorcinol selectively recognize lithium ions in dioxane-water solutions at high pH. Derivatives of azoles recognize lithium in neutral acetonitrile solutions. Stability constants of the respective complexes were determined. Thc chromoionophores with phenol residues were immobilized in an organic-inorganic hybrid xerogels. Opposite to solutions, some of these materials recognize lithium cations on contact with their neutral aqueous salt solutions.

PL

Syntezowano zdolne do oddysocjowania protonu związki koronowe o konstytucji zbliżonej do lakowych barwników azowych i badano ich właściwości. Cząsteczki tych chromojonoforów zawierają fragment polioksyetylenowy i dwa chromofory azowe tworzące makrocykl oraz fenolową grupę OH. Jako grupę zdolną do oddysocjowania protonu wybrano też resztę NH azoli. Wiele z tych związków to wartościowe odczynniki do rozpoznawania kationów litu charakteryzujące się znacznym rozdzieleniem pasm widmowych dla ligandów i ich kompleksów z kationami metali alkalicznych. Pochodne fenoli i rezorcynolu selektywnie rozpoznają jony litu w roztworach woda-dioksan przy wysokich wartościach pH. Chromojonofory z fragmentem fenolowym były immobilizowane w hybrydowych nieorganiczno-organicznych kserożelach. W odróżnieniu od roztworów, niektóre z tych materiałów rozpoznają sole litu po zetknięciu z ich obojętnymi wodnymi roztworami.

14

Measurement and correlation of the solubility of crown ethers in selected organic solvents

Domańska U.

Polish Journal of Chemistry

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1998

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Vol. 72, nr 5

925-939

EN

The solid-liquid equilibrium (SLE), of 13 binary mixtures {18-crown-6(1) + selected organics solvents: benzene, 1-heptene, 1-heptyne, tert-butanol, ethyl mathyl ketone, methyl n-propyl ketone, isobutyl methyl ketone, 1-hexanal, epichlorohydrin, DMSO, 1,1,1-trichloroethane, tetrachloroethylene, 1-chlorobutane (2)} have been determined between 240-315 K. The data have been correlated with three G(E) equations: Wilson, NRTL and UNIQUAC. Moreover published earlier nineteen sets of SLE data for different crown ether: {12-crown-4 or 18-crown-6, or dibenzo-8-crown-6, or dibenzo-24-crown-8(1) + organic solvent (2)} published earlier have been examined, using the same correlation equations. The best cerrelation of the solubility data have been obtained by Wilson's equation, where the root-mean-square deviation of the solubility temperatures varied from 0.44 K to 1,87 K and were dependent on the solute calculated. In the calculations, the existence of solid-solid forst-order phase transition in 18-crown-6 and dibenzo-24-crown-8 have been taken into consideration.

15

Zastosowanie polimerów jako katalizatorów w reakcjach katalizy międzyfazowej. Cz. II. Katalizatory polimerowe - sole oniowe, związki makrocykliczne oraz rozpuszczalniki aprotyczne na matrycy polimerowej

Bogdał D., Pielichowski J.

Polimery

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1998

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T. 43, nr 1

11-17

PL

Przedstawiono przegląd literatury dotyczący układów polimerowych, które mogą być wykorzystywane do katalizowania reakcji w warunkach katalizy międzyfazowej (PCT). Za-stosowanie katalizatorów PCT na matrycy polimerowej pozwala na uniknięcie wielu problemów związanych z oddzielaniem katalizatora po reakcji i umożliwia jego recykling. Mimo, że w większości przypadków jako ugrupowanie aktywne na matrycy polimerowej wykorzystuje się klastyczne katalizatory PCT (sole oniowe, etery koronowe i kryptandy), istnieje tu znacznie więcej czynników mających wpływ na ich aktywność niż w przypadku odpowiednich katalizatorów małocząsteczkowych. Do czynników takich zalicza się np. stopień usieciowania matrycy, stężenie aktywnych ugrupowań i ich lipofilowość, długość łańcucha metylenowego łączącego matrycę z grupą aktywną. Interesującą grupę stanowią również rozpuszczalniki aprotyczne na matrycy polimerowej (sulfotlenek dimetylowy, sul-folan, N,N-dimetyloformamid i in.); wykorzystuje się je jako współrozpuszczalniki o działaniu katalitycznym w reakcjach PCT.

EN

Summary - A review covering polymer systems applicable as PTC, subdivided into three groups: (i) polymeric phosphoramides, acetamides, sulfoxides, sulfones and pyridines used as PTC in the unmodified form (ineffective m the monomer form); (ii) onium salts, crown ethers and cryptands supported on insoluble polymer matrices; (iii) soluble polymers containing aprotic solvent moieties such as dimethyl sulfoxide, sulfolane, N,N-dimethyl formamide, N,N-dimethyl acetamide, etc. Although group ii includes classical PTC species, catalyst activity is still affected by structural factors like the degree of crosslinking of polymer matrix, concentration and lipophilicity of active groups, length of the methylene chain spacer between the polymer and the active group, etc. Immobilization on a polymer matrix eliminates problems of separation and recycling of PTC catalysts. Mechanical strength and chemical stability of immobilized PTC are then crucial.

16

N-(diethylthiophosphoryl)-aza[18]crown-6: synthesis and ability of solvent extraction toward lead(II), zinc(II) and cadmium(II) metal cations

Kozlowska J., Miroshnichenko S.

Ars Separatoria Acta

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2012/2013

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No. 9/10

7--14

EN

This work presents the synthesis of a strongly hydrophobic, functionalized monaza crown ether, i.e., lariat ether, namely N-(diethylthiophosphoryl)-aza[18]crown-6 and its application as ion extractant in solvent extraction systems. The synthesis of thiophosphorylated aza[18]crown-6 was performed with good yield. Separation systems have been successfully developed to extract Pb(II), Cd(II) and Zn(II) into organic phase, i.e., chloroform with the crown ethers: aza[18]crown-6 and N-(diethylthiophosphoryl)-aza[18] crown-6 as extractants. The selectivity order in both crown ethers was Pb(II) >> Cd(II) > Zn(II). The obtained results suggest that N-(diethylthiophosphoryl)-aza[18]crown-6 can be used for the selective removal of Pb(II) at lower pH values than aza[18]crown-6.