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Wyświetlanie 1-3 z 3
Tytuł:
Selective removal of Cu(II), Co(II), Zn(II), and Ni(II) with ionizable dibenzo-16-crown-5 and dibenzo-19-crown-6 lariat ethers as ion carriers in polymer inclusion membrane transport
Autorzy:
Kozłowski, C. A.
Walkowiak, W.
Powiązania:
https://bibliotekanauki.pl/articles/346931.pdf
Data publikacji:
2007
Wydawca:
Politechnika Bydgoska im. Jana i Jędrzeja Śniadeckich. Wydział Technologii i Inżynierii Chemicznej
Tematy:
polymer inclusion membrane
competitive transport
copper(II)
cobalt(II)
zinc(II)
nickel(II)
enthalpy of formation
Derivatives of dibenzo-16-crown-5 and dibenzo-19-crown-6
Opis:
A selective removal of transition metal cations, i.e. Cu(II), Co(II), Zn(II), and Ni(II), with ionizable dibenzo-16-crown-5 and dibenzo-19-crown-6 lariat ethers as ionic carriers in transport across polymer inclusion membrane has been presented. The competitive transport from aqueous nitrate solutions containing metal ions at concentrations of 0.0010 M at pH 4.0 and 7.0 through the cellulose triacetate membrane with 0.5 M lariat ether 1 and 2 (based on a plasticizer) as the ion carrier and o-nitrophenyl pentyl ether (ONPPE) as the plasticizer into 0.5 M hydrochloric solution was performed. For pH = 4.0 and 7.0 of source aqueous phases the selectivity orders were as follows: Cu(II) > Co(II) > Zn(II) > Ni(II), and Cu(II) > Zn(II), Ni(II), Co(II), respectively. The semi-empirical equation was used for calculations of enthalpy formation for complexes of lariat ethers studied with transition metal cations. The two possibilities of metal cation-lariat ether coordination were assumed, i.e. via the crown ether cavity or ionizable carboxylic group. We found that for the both lariat ethers studied at pH 4.0 of source phase the transport rate linearly decreases with the enthalpy of formation increase. This correlation confirms that the observed behavior is connected with the stability of complexes formed by interaction of the lariat ether ring and the transition metal cations studied.
Źródło:
Ars Separatoria Acta; 2007, 5; 19-26
1731-6340
Pojawia się w:
Ars Separatoria Acta
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Zinc(II) selective removal from other transition metal ions by solvent extraction and transport through polymer inclusion membranes with D2EHPA
Autorzy:
Ulewicz, M.
Walkowiak, W.
Pośpiech, B.
Powiązania:
https://bibliotekanauki.pl/articles/346997.pdf
Data publikacji:
2003
Wydawca:
Politechnika Bydgoska im. Jana i Jędrzeja Śniadeckich. Wydział Technologii i Inżynierii Chemicznej
Tematy:
polymer inclusion membrane
solvent extraction
zinc(II)
cobalt(II)
nickel(II)
copper(II)
cadmium(II)
Opis:
An experimental investigation concerns zinc(II), cobalt(II), nickel(II), copper(II) and cadmium(II) ions separation from aqueous chloride solutions by solvent extraction and transport through polymer inclusion membrane (PIM) processes. The selective transport of metal ions from the aqueous chloride source phase through PIM containing cellulose triacetate (support), o-nitrophenyl pentyl ether (plasticizer) and di(2-ethylhexyl)phosphoric acid (ion carrier) is shown. Zn(II) can be effectively removed from dilute aqueous chloride solutions by its transport through PIMs with di(2-ethylhexyl)phosphoric acid as the ionic carriers into 1.0 M HCl as the receiving phase. The transport selectivity of Zn(II) over Co(II), Ni(II), Cu(II) and Cd(II) decreases while the pH of the solution increases in the source phase. Also, by solvent extraction, Zn(II) can be selectively removed from dilute aqueous chloride solutions.
Źródło:
Ars Separatoria Acta; 2003, 2; 47-55
1731-6340
Pojawia się w:
Ars Separatoria Acta
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Lead(II) removal from aqueous solutions by solvent extraction with tetracarboxylresorcin[4]arene
Autorzy:
Konczyk, J.
Kozlowski, C.
Walkowiak, W.
Powiązania:
https://bibliotekanauki.pl/articles/110670.pdf
Data publikacji:
2013
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
solvent extraction
lead(II)
zinc(II)
cadmium(II)
resorcinarene
Opis:
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).
Źródło:
Physicochemical Problems of Mineral Processing; 2013, 49, 1; 213-222
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-3 z 3

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