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Extraction properties of tetraheptylresorcin[4]arenes in relation to Cr(III) ions

Konczyk J., Miroshnychenko S., Kozlowski C.

Physicochemical Problems of Mineral Processing

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2016

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Vol. 52, iss. 2

835--844

EN

Resorcin[4]arene-based ligand bearing four heptyl chains at the lower rim of the molecule was prepared and modified by four tetradietoxyphosphoryl groups in the upper rim. The compounds obtained were characterized by NMR spectroscopy and their extractability toward chromium(III) ions was studied. The influence of process parameters such as the pH of aqueous phase, agitation time and also extractant’s structure and concentration on efficiency of Cr(III) ions solvent extraction is presented. The highest yield of Cr(III) solvent extraction was obtained for two-hour agitation time of 5.010−4 M metal solution of pH 5.0 and 5.010−3 M chloroform solution of the tetradietoxyphosphorylated derivative of heptyl-resorcin[4]arene. Under optimal conditions, competitive solvent extraction of Cr(III), Zn(II), and Cd(II) ions was performed and separation factor values were established as 77.0 and 24.9 for Cr(III)/Cd(II) and Cr(III)/Zn(II) ions pairs, respectively. The stoichiometry of formed metal-ligand complexes 1:1 was found by classical slope analysis method.

2

Selective removal of Ag(I) and Cu(II) by plasticizer membranes with n-(diethylthiophosphoryl)-aza[18]crown-6 as a carrier

Kolodziejska M., Kozlowski C., Kozlowska J., Ulewicz M.

Physicochemical Problems of Mineral Processing

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2014

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Vol. 50, iss. 1

237--247

EN

The competitive transport of equimolar mixtures of Ag(I) and Cu(II) ions from aqueous source phase (cMe = 0.001 mol/dm3) across polymer inclusion membranes PIMs with N-(diethylthiophosphoryl)aza[18]crown-6 as ion carriers, was studied. The influence of pH of source phase and metal concentration on an efficiency of silver(I) transport through polymer inclusion membranes containing cellulose triacetate as the support and o-nitrophenyl pentyl ether as the plasticizer was studied. The transport selectivity order for the PIM with N-(diethylthiophosphoryl)-aza[18]crown-6 was: Ag(I) >> Cu(II). The metal cations transport rate can be explained by size and nature of substituent in lariat ether molecule, which prefer formation of Ag(I) complex in the membrane phase.

3

Separation of lead(II) and copper(ii) by plasticizer membranes with sulphur ana-logus of phosphinic acids as carriers

Kolodziejska M., Kozlowski C., Ulewicz M.

Physicochemical Problems of Mineral Processing

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2013

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Vol. 49, iss. 1

267--276

EN

Investigation of selective removal of Pb(II) and Cu(II) from acidic nitrate aqueous solutions using transport across polymer inclusion membranes PIMs was performed. The sulphur analogus of phosphinic acids, i.e. bis(2,4,4-trimethylpentyl)monothiophosphinic acid (1) and tert-butyl(phenyl)- phosphinothioic acid (2) as well as their mixture were incorporated into polymer inclusion membranes composed of cellulose triacetate as a support and o-nitrophenyl octyl ether as a plasticizer. In the experi-ments the transport of Cu(II) across PIM with 1 was rapid and complete, however the lead(II) removal increased with increased membrane saturation. Selective transport of Cu(II) over Pb(II) through PIMs with binary carrier system (1 + 2) was observed; the selectivity order was: Cu(II) >> Pb(II). At tempera-ture of 50C the selectivity coefficient Cu(II)/Pb(II) for membrane with binary carriers was the highest and was equal to 758.

4

Lead(II) removal from aqueous solutions by solvent extraction with tetracarboxylresorcin[4]arene

Konczyk J., Kozlowski C., Walkowiak W.

Physicochemical Problems of Mineral Processing

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2013

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Vol. 49, iss. 1

213--222

EN

A novel tetracarboxylresorcin[4]arene was synthesized and its selective complexing ability towards Pb(II) ions was examined. The influence of several parameters such as pH of aqueous phase, agitation time, extractant and modifier concentrations on solvent extraction of Pb(II) ions from the aque-ous nitrate phase into chloroform organic phase was studied. The stoichiometry of the formed metal-ligand complexes was established by slope analysis. Pb(II) ions were quantitatively extracted in the form of 2:1 Pb(II)-resorcin[4]arene complex from aqueous solutions of pH 5.5 to the solution of ligand in chloroform. Competitive solvent extraction experiments in the presence of Zn(II) and Cd(II) ions were also carried out and high selectivity of the extractant towards Pb(II) over Zn(II) and Cd(II) was found. The selectivity order was: Pb(II) >> Cd(II) > Zn(II).

5

Influence of palladium chemical structure on hydrogen sensing properties of carbonaceous–palladium thin films

Kaminska A., Krawczyk S., Kozlowski C.

Optica Applicata

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2013

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Vol. 43, nr 4

633--640

EN

In this work we investigate nanocomposite carbonaceous–palladium (C–Pd) films prepared by physical vapor deposition. Such films are promising materials for hydrogen sensor applications. This is related to the highly selective hydrogen absorption by palladium nanocrystallites. The C–Pd films obtained in various technological conditions differ in structure and electrical properties. These films were characterized by SEM, EDS and FTIR spectroscopy. FTIR spec-troscopy was used to determine the amount of palladium acetate and fullerene, incompletely decomposed during the deposition process. FTIR spectra enabled us to explain the differences in C–Pd films resistance based on palladium chemical structure. The possibility of the application of C–Pd films as active layers in hydrogen sensors was also studied. The results showed that synthesized C–Pd films containing palladium nanograins could be used for hydrogen sensing.