H. Korkmaz Alpoguz

Transport of Hg2+ through bulk liquid membrane using a bis-calix[4]arene nitrile derivative as carrier: kinetic analysis

The transport of Hg(II) ions from an aqueous solution into an aqueous receiving solution through a bulk liquid membrane containing a bis-calix[4]arene nitrile derivative (1) as a carrier was examined. The kinetic parameters were analyzed assuming two consecutive, irreversible first-order reactions. The influence of temperature, the solvent and stirring rate on the kinetic parameters (k1, k2, Rmmax, tmax, Jdmax, Jamax) has also been investigated. The membrane entrance rate, k1, and the membrane exit rate, k2, increased with increasing temperature and stirring rate. The membrane entrance and exit rate constants are found to vary in the order CH2Cl2 > CHCl3 > CCl4. For the maximum membrane exit flux, Jamax, the activation energy was found from the slope of the linear Arrhenius relationship to be 9.95 kcal mol−1, which indicates that the process is controlled by species diffusion.

Kinetics of Mercury(II) Transport Through a Bulk Liquid Membrane Containing Calix[4]arene Derivatives as Carrier

The kinetics of transport of mercury (II) ions through a bulk liquid membrane (chloroform) containing calix[4]arene nitrile derivatives as a carrier was examined at different temperatures and different stirring rates. The kinetics of mercury (II) transport could be analyzed in the formalism of two, consecutive, irreversible first-order reactions. The influence of temperature and stirring rate on kinetic parameters also have been investigated. The membrane entrance rate, k1, and the membrane exit rate, k2, increased with increasing temperature and increasing stirring rate. For maximum membrane exit fluxes, the activation energies were found as 1.923 ± 0.15 and 2.112 ± 0.2 kj/mol, for ligand carrier 1 and 2, respectively. The values for the found activation energy indicate that the process is controlled by species diffusion.

Liquid Membrane Transport of Hg(II) by an Azocalix[4]arene Derivative

Abstract A kinetic study of Hg(II) transport from an aqueous donor solution into an aqueous acceptor solution through a liquid membrane containing 25,26,27–tribenzoyloxy‐28‐hydroxy‐5,11,17,23‐tetra‐(4‐n‐butylphenylazo)calix[4]arene 1 as a carrier was studied. The kinetic parameters (k 1, k 2, R m max, t max, J d max, J a max) for the transport were investigated in terms of the effect of temperature, the stirring rate, the carrier concentration, and the type of solvent. The kinetics of transport was analyzed in the formalism of two consecutive irreversible first‐order reactions. The membrane entrance rate, and exit rate constants were increased with increasing of temperature stirring rate, and carrier concentration. The membrane entrance rate and exit rate constants depended on the type of solvent and was found to be in order of CH2Cl2> CHCl3> CCl4. The activation energy values are calculated as 30.67±2.64 and 57.33±4.90 kj mol−1 for extraction and reextraction, respectively. The values of calculated activation energy indicate that the process is diffusionally controlled by species.

Transport of metals through a liquid membrane containing calix[4]arene derivatives as carrier

Co-transport of metals (Hg2+, Pb2+, Na+) from an aqueous solution into an aqueous-receiving solution through a bulk liquid membrane containing calix[4]arene nitrile derivatives as carriers was investigated. Kinetic parameters were analyzed with consecutive irreversible first-order reactions and the effect of solvents such as CH2Cl2, CHCl3, and CCl4 was also examined. The transport rates show that both nitrile derivatives are efficient and selective for Hg(II) ions with respect to Na+ and Pb2+ ions and the dinitrile derivative is found to be a better carrier than the tetranitrile one. The membrane entrance- and exit rate-constants depend on the solvent type and are found to be in the order CH2Cl2>CHCl3>CCl4. A remarkable difference was also observed of the same order for fluxes.

Transport Kinetics of Hg2+ Through Bulk Liquid Membrane Using Calix[4]arene Ketone Derivative as Carrier

Abstract In this article, calix[4]arene ketone derivative was used as a carrier to transport Hg2+ ions from an aqueous solution into an aqueous receiving solution. The kinetic parameters (k 1, k 2, R m max, t max, J d max, J a max) were investigated with influence of temperature, the solvent, and stirring rate and analyzed in the formation of two consecutive, irreversible first order reactions. The membrane entrance rate, k 1, and the membrane exit rate, k 2, constants were increased with temperature and stirring rate and found to be dependent on the solvent type in the order CH2Cl2 > CHCl3 > CCl4. The activation energy was obtained as 5.28 kcal/mol from the slope of the Arrhenius plot for the case of maximum membrane exit flux, J a max. This value indicates that the process is controlled by species diffusion.

Transport of Hg2+ Ions across a Supported Liquid Membrane Containing Calix[4]arene Nitrile Derivatives as a Specific Ion Carrrier

Abstract The transport behavior of Hg2+ from aqueous solution through a flat‐sheet‐supported liquid membrane (SLM) has been investigated by using of calix[4]arene derivatives (1 and 2) as carriers and Celgrad 2400 and 2500 as the solid support. The effect of solvent type and anions such as chloride and nitrate ions on the transport of Hg2+ was examined. Danesi mass transfer model was used to calculate the permeability coefficients for each parameter studied. The highest values of permeability were obtained with 2‐nitrophenyl ethyl ether (NPOE) solvent and the influence was found to be in the order, NPOE>chloroform>xylene. The transport efficiency on the supported liquid membrane was dependent on the type of carrier, its characteristics, and the type of the solvent.

Facilitated Supported Liquid Membrane Transport of Hg2+ Using Calix[4]arene Derivatives

The transport behavior of Hg2+ from aqueous solution through a flat‐sheet supported liquid membrane has been investigated by the use of calix[4]arene derivatives (1 and 2) as carriers and Celgard 2400 and Celgard 2500 as the solid support. The effect of solvent type and anions such as chloride and nitrate ions on the transport of Hg2+ was examined. A Danesi mass transfer model was used to calculate the permeability coefficients for each parameter studied. The highest values of permeability were obtained with 2‐nitrophenyloctyl‐ether (NPOE) solvent and the influence was found to be in the order of NPOE>chloroform>xylene. The transport efficiency on the liquid membrane transport was dependent on the type of solvent, anion, and carrier.

Facilitated Transport of Cr(VI) through Polymer Inclusion Membrane System Containing Calix[4]arene Derivative as Carrier Agent

Chromium(VI) is one of the major toxic elements present in environmental samples. The polymer inclusion membrane (PIM), has been developed to provide metal ion transport with high selectivity. This study was conducted to discover efficient methods for removing Cr(VI) from wastewater. A functionalized calix[4]arene carrier 1 in a PIM system was used to transport Cr(VI) from an acidic aqueous donor phase solution to an acceptor phase that contained an acetic acid/ammonium acetate solution at pH 6. The prepared PIM was characterized with Fourier Transform Infrared (FT-IR) spectroscopy and the Atomic Force Microscopy (AFM) techniques as well as with contact angle measurements. The efficiency of Cr(VI) transport through the PIM was investigated by studying the effects of carrier concentration on the membrane phase as well as by measuring the amount of plasticizer in the membrane, the pH in the acceptor phase and the membranes stability and thickness. The kinetic parameters were calculated as rate constant (k), permeability coefficient (P), flux (J) and diffusion coefficient (Do). The transport efficiency of Cr(VI) was observed to be 98.61% after 10 h under optimized conditions. The experimental results show that Cr(VI) can transport from the donor phase to the acceptor phase with high efficiency through the PIM. The results also suggest that the transport efficiency of the PIM was reproducible and that a PIM is effective for long-term separation processes.

ABSORPTIVE IONOPHORES FOR Fe3+ CATION BY PARENT CALIX[n]ARENES

The absorption of Fe3+ ion from the aqueous phase to the solid phase was carried out by using p-tert-butyl calix[6]arene (L1), calix[6]arene (L2), p-tert-butyl calix[8]arene (L3), and calix[8]arene (L4). The effect of varying pH upon the absorption capability of parent calixarenes was examined. It was found that the compounds (L1, L2, L3, and L4) showed the highest extractability toward Fe3+ ion at 4.5–5.4. The calixarene L2 shows a strong binding ability to Fe3+ ion. Based on the continuous variation method, calixarene L2 formed 1:1 complex with Fe3+ ion.

A novel electro-driven membrane for removal of chromium ions using polymer inclusion membrane under constant D.C. electric current.

In this study, the use of polymer inclusion membrane under constant electric current for the removal of Cr(VI) from water has investigated for the first time. Transport of Cr(VI) is performed by an electric current from the donor phase to the acceptor phase with a constant electric current of 0.5A. The optimized membrane includes of 12.1% 2-nitrophenyl octyl ether (2-NPOE), 77.6% cellulose triacetate (CTA), 10.3% tricapryl-methylammonium chloride (Aliquat 336) as a carrier. We tested the applicability of the selected membrane for Cr(VI) removal in real environmental water samples and evaluated its reusability. Electro membrane experiments were carried out under various parameters, such as the effect of electro membrane voltage at constant DC electric current; electro membrane current at constant voltage, acceptor phase pH, and stable electro membrane; and a comparison of polymer inclusion membrane and electro membrane transport studies. The Cr(VI) transport was achieved 98.33% after 40min under optimized conditions. An alternative method has been employed that eliminates the changing of electrical current by the application of constant electric current for higher reproducibility of electro membrane extraction experiments by combining the excellent selective and long-term use features of polymer inclusion membrane.